Printing System Assemblies and Methods

ABSTRACT

The present teachings disclose various embodiments of a printing system for printing a substrate, in which the printing system can be housed in a gas enclosure, where the environment within the enclosure can be maintained as a controlled printing environment. A controlled environment of the present teachings can include control of the type of gas environment within the gas enclosure, the size and level particulate matter within the enclosure, control of the temperature within the enclosure and control of lighting. Various embodiments of a printing system of the present teachings can include a Y-axis motion system and a Z-axis moving plate that are configured to substantially decrease excess thermal load within the enclosure by, for example, eliminating or substantially minimizing the use of conventional electric motors.

CROSS REFERENCE TO RELATED CASES

This application is a continuation case of U.S. Ser. No. 15/354,927,filed Nov. 17, 2016. U.S. Ser. No. 15/354,927 is a continuation case ofU.S. Ser. No. 14/738,785, filed Jun. 12, 2105. U.S. Ser. No. 14/738,785claims benefit to each of the following: (1) U.S. ProvisionalApplication No. 62/013,433, filed Jun. 17, 2014; (2) U.S. ProvisionalApplication No. 62/021,390, filed Jul. 7, 2014; (3) U.S. ProvisionalApplication No. 62/037,494, filed Aug. 14, 2014; (4) U.S. ProvisionalApplication No. 62/013,440, filed Jun. 17, 2014; (5) U.S. ProvisionalApplication No. 62/021,563, filed Jul. 7, 2014; (6) U.S. ProvisionalApplication No. 62/044,165, filed Aug. 29, 2014; (7) U.S. ProvisionalApplication No. 62/092,721, filed Dec. 16, 2014. Each application listedin this section is incorporated herein by reference in its entirety.

FIELD

The present teachings relate to various embodiments of a printing systemthat can be maintained in a gas enclosure system defining an interiorthat has an inert, substantially low-particle environment.

Overview

Interest in the potential of organic light-emitting diode (OLED) displaytechnology has been driven by OLED display technology attributes thatinclude demonstration of display panels that have highly saturatedcolors, are high-contrast, ultrathin, fast-responding, and energyefficient. Additionally, a variety of substrate materials, includingflexible polymeric materials, can be used in the fabrication of OLEDdisplay technology. Though the demonstration of displays for smallscreen applications, primarily for cell phones, has served to emphasizethe potential of the technology, challenges remain in scaling highvolume manufacturing across a range of substrate formats in high yield.

With respect to scaling of formats, a Gen 5.5 substrate has dimensionsof about 130 cm×150 cm and can yield about eight 26″ flat paneldisplays. In comparison, larger format substrates can include using Gen7.5 and Gen 8.5 mother glass substrate sizes. A Gen 7.5 mother glass hasdimensions of about 195 cm×225 cm, and can be cut into eight 42″ or six47″ flat panel displays per substrate. The mother glass used in Gen 8.5is approximately 220 cm×250 cm, and can be cut to six 55″ or eight 46″flat panel displays per substrate. One indication of the challenges thatremain in scaling of OLED display manufacturing to larger formats isthat the high-volume manufacture of OLED displays in high yield onsubstrates larger than Gen 5.5 substrates has proven to be substantiallychallenging.

In principle, an OLED device may be manufactured by the printing ofvarious organic thin films, as well as other materials, on a substrateusing an OLED printing system. Such organic materials can be susceptibleto damage by oxidation and other chemical processes. Housing an OLEDprinting system in a fashion that can be scaled for various substratesizes and can be done in an inert, substantially low-particle printingenvironment can present a variety of engineering challenges.Manufacturing tools for high throughput large-format substrate printing,for example, such as printing of Gen 7.5 and Gen 8.5 substrates, requiresubstantially large facilities. Accordingly, maintaining a largefacility under an inert atmosphere, requiring gas purification to removereactive atmospheric species, such as water vapor and oxygen, as well asorganic solvent vapors, as well as maintaining a substantiallylow-particle printing environment, has proven to be significantlychallenging.

As such, challenges remain in scaling high volume manufacturing of OLEDdisplay technology across a range of substrate formats in high yield.Accordingly, there exists a need for various embodiments a gas enclosuresystem of the present teachings that can house an OLED printing system,in an inert, substantially low-particle environment, and can be readilyscaled to provide for fabrication of OLED panels on a variety ofsubstrates sizes and substrate materials. Additionally, various gasenclosure systems of the present teachings can provide for ready accessto an OLED printing system from the exterior during processing and readyaccess to the interior for maintenance with minimal downtime.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the features and advantages of the presentdisclosure will be obtained by reference to the accompanying drawings,which are intended to illustrate, not limit, the present teachings. Inthe drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents.

FIG. 1A is a front perspective view of view of a gas enclosure assemblyin accordance with various embodiments of the present teachings. FIG. 1Bdepicts an exploded view of various embodiments of a gas enclosureassembly as depicted in FIG. 1A. FIG. 1C depicts an expanded isoperspective view of the printing system depicted in FIG. 1B. FIG. 1D isa an expanded perspective view of an auxiliary enclosure of a gasenclosure system according to various embodiments of the presentteachings.

FIG. 2A is a front perspective view of view of a gas enclosure assemblyin accordance with various embodiments of the present teachings. FIG. 2Bis a partially exploded perspective view of an auxiliary enclosure of agas enclosure system according to various embodiments of the presentteachings. FIG. 2C is a partially exploded top perspective view of anauxiliary enclosure of a gas enclosure system according to variousembodiments of the present teachings.

FIG. 3 is an expanded iso view of a printing system according to thepresent teaching, showing a Y-axis motion system.

FIG. 4A is a top view of a Y-axis motion system according to variousembodiments of systems and methods of the present teachings. FIG. 4B isan expanded partial top view of FIG. 4A.

FIG. 5A is an iso view of a Y-axis motion system according to variousembodiments of systems and methods of the present teachings. FIG. 5B isa long section view of FIG. 5A.

FIG. 6 is side view of a carrier assembly side frame with a grippermotion control assembly mounted thereupon.

FIG. 7A is an iso view of a voice coil assembly according to variousembodiments of systems and methods of the present teachings. FIG. 7B isa side view of a voice coil assembly.

FIG. 8 is a top view of a Y-axis motion system according to variousembodiments of systems and methods of the present teachings, indicatingtwo section views.

FIG. 9 is a section view of a voice coil assembly, as indicated in FIG.8.

FIG. 10 is a section view of a center pivot assembly, as indicated inFIG. 8.

FIG. 11 is a schematic representation of a closed-loop control circuitproviding pneumatic counterbalance to a Z-axis motor according tovarious embodiments of systems and methods of the present teachings.

FIG. 12A is an iso perspective view of a Z-axis moving plate withpneumatic lift elements and FIG. 12B is a front perspective view aZ-axis moving plate with pneumatic lift elements in accordance withvarious embodiments of the present teachings.

FIG. 13 is a schematic representation of an enclosed printing systemthat can utilize various embodiments of an ink delivery system accordingto the present teachings.

FIG. 14 is a schematic representation of a bulk ink delivery systemaccording to various embodiments of the present teachings.

FIG. 15 is a schematic representation of a bulk ink delivery systemaccording to various embodiments of the present teachings.

FIG. 16 is a schematic representation of a local ink delivery system foran enclosed printing system according to various embodiments of thepresent teachings.

FIG. 17 is a schematic representation of a local ink delivery system inflow communication with a printhead ink delivery system for an enclosedprinting system according to various embodiments of the presentteachings.

FIG. 18A is a bottom perspective view of a printhead assembly mounted onan X-axis bridge. FIG. 18B is an expanded view of FIG. 18A.

FIG. 19A is a front top perspective view of a printhead device, whileFIG. 19B is a front bottom perspective view of a printhead device,according to various embodiments of the present teachings. FIG. 19C is afront top perspective view of a mounting plate for printhead device,while FIG. 19D is a front bottom perspective view of a printhead devicemounted in a mounting assembly, according to various embodiments of thepresent teachings.

FIG. 20 is a schematic view of various embodiments of gas enclosureassembly and related system components the present teachings.

FIG. 21A and FIG. 21B are schematic views of various embodiments of anenclosed printing system and components for integrating and controllinggas sources such as can be used to establish a controlled gasenvironment in a gas enclosure, which various embodiments can include asupply of pressurized gas for use with a floatation table.

FIG. 22A through FIG. 22C are schematic views of various embodiments ofan enclosed printing system and components for integrating andcontrolling gas sources such as can be used to establish a controlledgas environment in a gas enclosure, which various embodiments caninclude a blower loop to provide, for example, pressurized gas, as wellas a vacuum source for use with a floatation table.

DETAILED DESCRIPTION OF THE DISCLOSURE

The present teachings disclose various embodiments of a printing systemfor printing a substrate, in which the printing system can be housed ina gas enclosure, where the environment within the enclosure can bemaintained as a controlled printing environment. A controlledenvironment of the present teachings can include control of the type ofgas environment within the gas enclosure, the size and level particulatematter within the enclosure, control of the temperature within theenclosure and control of lighting. Various embodiments of a printingsystem of the present teachings can include a Y-axis motion system and aZ-axis moving plate assembly that are configured to substantiallydecrease excess thermal load within the gas enclosure, for example, byeliminating or substantially minimizing the use of conventional electricmotors. Additionally, various embodiments of a Y-axis motion system ofthe present teachings can include a gripper motion control assembly of aY-axis motion system configured to provide dynamic rotation of theorientation of a substrate about the theta-Z (θ-Z) axis during Y-axistravel to maintain a high degree of precision for substrate orientationparallel to the axis of travel.

Various embodiments of a gas enclosure assembly can be sealablyconstructed and integrated with various components that provide a gascirculation and filtration system, a particle control system, a gaspurification system, and a thermal regulation system and the like toform various embodiments of a gas enclosure system that can sustain aninert gas environment that is substantially low-particle for processesrequiring such an environment. Various embodiments of a gas enclosurecan have a printing system enclosure and an auxiliary enclosureconstructed as a section of a gas enclosure assembly, which can besealably isolated from the printing system enclosure of a gas enclosure.Various embodiments of a printing system of the present teachings canhave a printhead management system enclosed in an auxiliary enclosure.Embodiments of printhead management system of the present teachings caninclude various devices and apparatuses for maintenance and calibrationof a printhead; the various devices and apparatuses each mounted on amotion system platform for the fine positioning of the various devicesand apparatuses relative to a printhead.

A printing system, such as printing system 2000 of FIG. 1B, shown inexpanded view in FIG. 1C, can be comprised of several devices andapparatuses, which allow the reliable placement of ink drops ontospecific locations on a substrate. Printing requires relative motionbetween the printhead assembly and the substrate. This can beaccomplished with a motion system, typically a gantry or split axis XYZsystem. Either the printhead assembly can move over a stationarysubstrate (gantry style), or both the printhead and substrate can move,in the case of a split axis configuration. In another embodiment, aprinthead assembly can be substantially stationary; for example, in theX and Y axes, and the substrate can move in the X and Y axes relative tothe printheads, with Z axis motion provided either by a substratesupport apparatus or by a Z-axis motion system associated with aprinthead assembly. As the printheads move relative to the substrate,droplets of ink are ejected at the correct time to be deposited in thedesired location on a substrate. A substrate can be inserted and removedfrom the printer using a substrate loading and unloading system.Depending on the printer configuration, this can be accomplished with amechanical conveyor, a substrate floatation table with a conveyanceassembly, or a substrate transfer robot with end effector. For variousembodiments of systems and methods of the present teachings, an Y-axismotion system can be based on an air-bearing gripper system.

For clearer perspective regarding substrate sizes that can be used inmanufacturing of various OLED devises, generations of mother glasssubstrate sizes have been undergoing evolution for flat panel displaysfabricated by other-than OLED printing since about the early 1990s. Thefirst generation of mother glass substrates, designated as Gen 1, isapproximately 30 cm×40 cm, and therefore could produce a 15″ panel.Around the mid-1990s, the existing technology for producing flat paneldisplays had evolved to a mother glass substrate size of Gen 3.5, whichhas dimensions of about 60 cm×72 cm. In comparison, a Gen 5.5 substratehas dimensions of about 130 cm×150 cm.

As generations have advanced, mother glass sizes for Gen 7.5 and Gen 8.5are in production for other-than OLED printing fabrication processes. AGen 7.5 mother glass has dimensions of about 195 cm×225 cm, and can becut into eight 42″ or six 47″ flat panels per substrate. The motherglass used in Gen 8.5 is approximately 220×250 cm, and can be cut to six55″ or eight 46″ flat panels per substrate. The promise of OLED flatpanel display for qualities such as truer color, higher contrast,thinness, flexibility, transparency, and energy efficiency have beenrealized, at the same time that OLED manufacturing is practicallylimited to G 3.5 and smaller. Currently, OLED printing is believed to bethe optimal manufacturing technology to break this limitation and enableOLED panel manufacturing for not only mother glass sizes of Gen 3.5 andsmaller, but at the largest mother glass sizes, such as Gen 5.5, Gen7.5, and Gen 8.5. One of the features of OLED panel display technologyincludes that a variety of substrate materials can be used, for example,but not limited by, a variety of glass substrate materials, as well as avariety of polymeric substrate materials. In that regard, sizes recitedfrom the terminology arising from the use of glass-based substrates canbe applied to substrates of any material suitable for use in OLEDprinting.

Manufacturing tools that in principle can allow for the printing of avariety of substrate sizes that includes large-format substrate sizes,can require substantially large facilities for housing such OLEDmanufacturing tools. Accordingly, maintaining an entire large facilityunder an inert atmosphere presents engineering challenges, such ascontinual purification of a large volume of an inert gas. Variousembodiments of a gas enclosure system can have a circulation andfiltration system internal a gas enclosure assembly in conjunction witha gas purification system external a gas enclosure that together canprovide continuous circulation of a substantially low-particulate inertgas having substantially low levels of reactive species throughout a gasenclosure system. According to the present teachings, an inert gas maybe any gas that does not undergo a chemical reaction under a defined setof conditions. Some commonly used non-limiting examples of an inert gascan include nitrogen, any of the noble gases, and any combinationthereof. Additionally, providing a large facility that is essentiallyhermetically sealed to prevent contamination of various reactiveatmospheric gases, such as water vapor and oxygen, as well as organicsolvent vapors generated from various printing process poses anengineering challenge. According to the present teachings, an OLEDprinting facility would maintain levels for each species of variousreactive species, including various reactive atmospheric gases, such aswater vapor and oxygen, as well as organic solvent vapors at 100 ppm orlower, for example, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1ppm or lower.

The need for printing an OLED panel in a facility in which the levels ofeach of a reactive species should be maintained at targeted low levelscan be illustrated in reviewing the information summarized in Table 1.The data summarized on Table 1 resulted from the testing of each of atest coupon comprising organic thin film compositions for each of red,green, and blue, fabricated in a large-pixel, spin-coated device format.Such test coupons are substantially easier to fabricate and test for thepurpose of rapid evaluation of various formulations and processes.Though test coupon testing should not be confused with lifetime testingof a printed panel, it can be indicative of the impact of variousformulations and processes on lifetime. The results shown in the tablebelow represent variation in the process step in the fabrication of testcoupons in which only the spin-coating environment varied for testcoupons fabricated in a nitrogen environment where reactive species wereless than 1 ppm compared to test coupons similarly fabricated but in airinstead of a nitrogen environment.

It is evident through the inspection of the data in Table 1 for testcoupons fabricated under different processing environments, particularlyin the case of red and blue, that printing in an environment thateffectively reduces exposure of organic thin film compositions toreactive species may have a substantial impact on the stability ofvarious ELs, and hence on lifetime. The lifetime specification is ofparticular significance for OLED panel technology, as this correlatesdirectly to display product longevity; a product specification for allpanel technologies, which has been challenging for OLED panel technologyto meet. In order to provide panels meeting requisite lifetimespecifications, levels of each of a reactive species, such as watervapor, oxygen, as well as organic solvent vapors, can be maintained at100 ppm or lower, for example, at 10 ppm or lower, at 1.0 ppm or lower,or at 0.1 ppm or lower with various embodiments of a gas enclosuresystem of the present teachings.

TABLE 1 Impact of inert gas processing on lifetime for OLED panelsProcess V Cd/A CIE (x, y) T95 T80 T50 Color Environment @ 10 mA/cm² @1000 Cd/m² Red Nitrogen 6 9 (0.61, 0.38) 200 1750 10400 Air 6 8 (0.60,0.39) 30 700 5600 Green Nitrogen 7 66 (0.32, 0.63) 250 3700 32000 Air 761 (0.32, 0.62) 250 2450 19700 Blue Nitrogen 4 5 (0.14, 0.10) 150 7503200 Air 4 5 (0.14, 0.10) 15 250 1800

In addition to providing an inert environment, maintaining asubstantially low-particle environment for OLED printing is ofparticular importance, as even very small particles can lead to avisible defect on an OLED panel. Particle control in a gas enclosuresystem can present significant challenges not presented for processesthat can be done, for example, in atmospheric conditions under open air,high flow laminar flow filtration hoods. For example, of a manufacturingfacility can require a substantial length of various service bundlesthat can be operatively connected from various systems and assemblies toprovide optical, electrical, mechanical, and fluidic connectionsrequired to operate, for example, but not limited by, a printing system.Such service bundles used in the operation of a printing system andlocated proximal to a substrate positioned for printing can be anongoing source of particulate matter. Additionally, components used in aprinting system, such as fans or linear motion systems that use frictionbearing, can be particle generating components. Various embodiments of agas circulation and filtration system of the present teachings can beused in conjunction with particle control components to contain andexhaust particulate matter. Additionally, by using a variety ofintrinsically low-particle generating pneumatically operated components,such as, but not limited by, substrate floatation tables, air bearings,and pneumatically operated robots, and the like, a low particleenvironment for various embodiments of a gas enclosure system can bemaintained.

Regarding maintaining a substantially low-particle environment, variousembodiments of a gas circulation and filtration system can be designedto provide a low particle inert gas environment for airborneparticulates meeting the standards of International StandardsOrganization Standard (ISO) 14644-1:1999, “Cleanrooms and associatedcontrolled environments—Part 1: Classification of air cleanliness,” asspecified by Class 1 through Class 5. However, controlling airborneparticulate matter alone is not sufficient for providing a low-particleenvironment proximal to a substrate during, for example, but not limitedby, a printing process, as particles generated proximal to a substrateduring such a process can accumulate on a substrate surface before theycan be swept through a gas circulation and filtration system.

Accordingly, in conjunction with a gas circulation and filtrationsystem, various embodiments of a gas enclosure system of the presentteachings can have a particle control system that can include componentsthat can provide a low-particle zone proximal to a substrate duringprocessing in a printing step. A particle control system for variousembodiments of a gas enclosure system of the present teachings caninclude a gas circulation and filtration system, alow-particle-generating X-axis linear bearing system for moving aprinthead assembly relative to a substrate, a service bundle housingexhaust system, and a printhead assembly exhaust system. For example, agas enclosure system can have a gas circulation and filtration systeminternal a gas enclosure assembly.

Various embodiments of systems and methods of the present teachings canmaintain a substantially low-particle environment providing for anaverage on-substrate distribution of particles of a particular sizerange of interest that does not exceed an on-substrate deposition ratespecification. An on-substrate deposition rate specification can be setfor each of a particle size range of interest of between about 0.1 μmand greater to about 10 μm and greater. In various embodiments systemsand methods of the present teachings, an on-substrate particledeposition rate specification can be expressed as a limit of the numberof particles deposited per square meter of substrate per minute for eachof a target particle size range.

Various embodiments of an on-substrate particle deposition ratespecification can be readily converted from a limit of the number ofparticles deposited per square meter of substrate per minute to a limitof the number of particles deposited per substrate per minute for eachof a target particle size range. Such a conversion can be readily donethrough a known relationship between substrates, for example, of aspecific generation-sized substrate and the corresponding area for thatsubstrate generation. For example, Table 2 below summarizes aspectratios and areas for some known generation-sized substrates. It shouldbe understood that a slight variation of aspect ratio and hence size maybe seen from manufacturer to manufacturer. However, regardless of suchvariation, a conversion factor for a specific generation-sized substrateand an area in square meters can be obtained any of a variety ofgeneration-sized substrates.

TABLE 2 Correlation between area and substrate size Generation ID X (mm)Y (mm) Area (m2) Gen 3.0 550 650 0.36 Gen 3.5 610 720 0.44 Gen 3.5 620750 0.47 Gen 4 680 880 0.60 Gen 4 730 920 0.67 Gen 5 1100 1250 1.38 Gen5 1100 1300 1.43 Gen 5.5 1300 1500 1.95 Gen 6 1500 1850 2.78 Gen 7.51950 2250 4.39 Gen 8 2160 2400 5.18 Gen 8 2160 2460 5.31 Gen 8.5 22002500 5.50 Gen 9 2400 2800 6.72 Gen 10 2850 3050 8.69

Additionally, an on-substrate particle deposition rate specificationexpressed as a limit of the number of particles deposited per squaremeter of substrate per minute can be readily converted to any of avariety of unit time expressions. It will be readily understood that anon-substrate particle deposition rate specification normalized tominutes can be readily converted to any other expression of time throughknow relationships of time, for example, but not limited by, such assecond, hour, day, etc. Additionally, units of time specificallyrelating to processing can be used. For example, a print cycle can beassociated with a unit of time. For various embodiments of a gasenclosure system according to the present teachings a print cycle can bea period of time in which a substrate is moved into a gas enclosuresystem for printing and then removed from a gas enclosure system afterprinting is complete. For various embodiments of a gas enclosure systemaccording to the present teachings a print cycle can be a period of timefrom the initiation of the alignment of a substrate with respect to aprinthead assembly to the delivery of a last ejected drop of ink ontothe substrate. In the art of processing, total average cycle time orTACT can be an expression of a unit of time for a particular processcycle. According to various embodiments of systems and methods of thepresent teachings, TACT for a print cycle can be about 30 seconds. Forvarious embodiments of systems and methods of the present teachings,TACT for a print cycle can be about 60 seconds. In various embodimentsof systems and methods of the present teachings, TACT for a print cyclecan be about 90 seconds. For various embodiments of systems and methodsof the present teachings, TACT for a print cycle can be about 120seconds. In various embodiments of systems and methods of the presentteachings, TACT for a print cycle can be about 300 seconds.

With respect to airborne particulate matter and particle depositionwithin a system, a substantial number of variables can impact developinga general model that may adequately compute, for example, anapproximation of a value for particle fallout rate on a surface, such asa substrate, for any particular manufacturing system. Variables such asthe size of particles, the distribution of particles of particular size;surface area of a substrate and the time of exposure of a substratewithin a system can vary depending on various manufacturing systems. Forexample, the size of particles and the distribution of particles ofparticular size can be substantially impacted by the source and locationof particle-generating components in various manufacturing systems.Calculations based on various embodiments of gas enclosure systems ofthe present teachings suggest that without various particle controlsystems of the present teachings, on-substrate deposition of particulatematter per print cycle per square meter of substrate can be between morethan about 1 million to more than about 10 million particles forparticles in a size range of 0.1 μm and greater. Such calculationssuggest that that without various particle control systems of thepresent teachings, on-substrate deposition of particulate matter perprint cycle per square meter of substrate can be between more than about1000 to about more than about 10,000 particles for particles in a sizerange of about 2 μm and greater.

Various embodiments of a low-particle gas enclosure system of thepresent teachings can maintain a low-particle environment providing foran average on-substrate particle distribution that meets an on-substratedeposition rate specification of less than or equal to about 100particles per square meter of substrate per minute for particles greaterthan or equal to 10 μm in size. Various embodiments of a low-particlegas enclosure system of the present teachings can maintain alow-particle environment providing for an average on-substrate particledistribution that meets an on-substrate deposition rate specification ofless than or equal to about 100 particles per square meter of substrateper minute for particles greater than or equal to 5 μm in size. Invarious embodiments of a gas enclosure system of the present teachings,a low-particle environment can be maintained providing for an averageon-substrate particle distribution that meets an on-substrate depositionrate specification of less than or equal to about 100 particles persquare meter of substrate per minute for particles greater than or equalto 2 μm in size. In various embodiments of a gas enclosure system of thepresent teachings, a low-particle environment can be maintainedproviding for an average on-substrate particle distribution that meetsan on-substrate deposition rate specification of less than or equal toabout 100 particles per square meter of substrate per minute forparticles greater than or equal to 1 μm in size. Various embodiments ofa low-particle gas enclosure system of the present teachings canmaintain a low-particle environment providing for an averageon-substrate particle distribution that meets an on-substrate depositionrate specification of less than or equal to about 1000 particles persquare meter of substrate per minute for particles greater than or equalto 0.5 μm in size. For various embodiments of a gas enclosure system ofthe present teachings, a low-particle environment can be maintainedproviding for an average on-substrate particle distribution that meetsan on-substrate deposition rate specification of less than or equal toabout 1000 particles per square meter of substrate per minute forparticles greater than or equal to 0.3 μm in size. Various embodimentsof a low-particle gas enclosure system of the present teachings canmaintain a low-particle environment providing for an averageon-substrate particle distribution that meets an on-substrate depositionrate specification of less than or equal to about 1000 particles persquare meter of substrate per minute for particles greater than or equalto 0.1 μm in size.

It is contemplated that a wide variety of ink formulations can beprinted within the inert, substantially low-particle environment ofvarious embodiments of a gas enclosure system of the present teachings.During the manufacture of an OLED display, an OLED pixel can be formedto include an OLED film stack, which can emit light of a specific peakwavelength when a voltage is applied. An OLED film stack structurebetween an anode and a cathode can include a hole injection layer (HIL),a hole transport layer (HTL), an emissive layer (EL), an electrontransport layer (ETL) and an electron injection layer (EIL). In someembodiments of an OLED film stack structure, an electron transport layer(ETL) can be combined with an electron injection layer (EIL) to form anETL/EIL layer. According to the present teachings, various inkformulations for an EL for various color pixel EL films of an OLED filmstack can be printed using, for example, inkjet printing. Additionally,for example, but not limited by, the HIL, HTL, EML, and ETL/EIL layerscan have ink formulations that can be printed using inkjet printing.

It is further contemplated that an organic encapsulation layer can beprinted on a substrate printing. It is contemplated that an organicencapsulation layer can be printed using inkjet printing, as inkjetprinting can provide several advantages. First, a range of vacuumprocessing operations can be eliminated because such inkjet-basedfabrication can be performed at atmospheric pressure. Additionally,during an inkjet printing process, an organic encapsulation layer can belocalized to cover portions of an OLED substrate over and proximal to anactive region, to effectively encapsulate an active region, includinglateral edges of the active region. The targeted patterning using inkjetprinting results in eliminating material waste, as well as eliminatingadditional processing typically required to achieve patterning of anorganic layer. An encapsulation ink can comprise a polymer including,for example, but not limited by, an acrylate, methacrylate, urethane, orother material, as well as copolymers and mixtures thereof, which can becured using thermal processing (e.g. bake), UV exposure, andcombinations thereof. As used herein polymer and copolymer can includeany form of a polymer component that can be formulated into an ink andcured on a substrate to form an organic encapsulation layer. Suchpolymeric components can include polymers, and copolymers, as well asprecursors thereof, for example, but not limited by, monomers,oligomers, and resins.

Various embodiments of a gas enclosure assembly can have various framemembers that are constructed to provide contour for a gas enclosureassembly. Various embodiments of a gas enclosure assembly of the presentteachings can accommodate an OLED printing system, while optimizing theworking space to minimize inert gas volume, and also allowing readyaccess to an OLED printing system from the exterior during processing.In that regard, various gas enclosure assemblies of the presentteachings can have a contoured topology and volume. As will be discussedin more detail subsequently herein, various embodiments of a gasenclosure can be contoured around a printing system base, upon which asubstrate support apparatus can be mounted. Further, a gas enclosure canbe contoured around a bridge structure of a printing system used for theX-axis movement of a carriage assembly. As a non-limiting example,various embodiments of a contoured gas enclosure according to thepresent teachings can have a gas enclosure volume of between about 6 m³to about 95 m³ for housing various embodiments of a printing systemcapable of printing substrate sizes from Gen 3.5 to Gen 10. By way afurther non-limiting example, various embodiments of a contoured gasenclosure according to the present teachings can have a gas enclosurevolume of between about 15 m³ to about 30 m³ for housing variousembodiments of a printing system capable of printing, for example, Gen5.5 to Gen 8.5 substrate sizes. Such embodiments of a contoured gasenclosure can be between about 30% to about 70% savings in volume incomparison to a non-contoured enclosure having non-contoured dimensionsfor width, length and height.

FIG. 1A depicts a perspective view gas enclosure assembly 1000 inaccordance with various embodiments of a gas enclosure assembly of thepresent teachings. Gas enclosure assembly 1000 can include front panelassembly 1200, middle panel assembly 1300 and rear panel assembly 1400.Front panel assembly 1200 can include front ceiling panel assembly 1260,front wall panel assembly 1240, which can have opening 1242 forreceiving a substrate, and front base panel assembly 1220. Rear panelassembly 1400 can include rear ceiling panel assembly 1460, rear wallpanel assembly 1440 and rear base panel assembly 1420. Middle panelassembly 1300 can include first middle enclosure panel assembly 1340,middle wall and ceiling panel assembly 1360 and second middle enclosurepanel assembly 1380, as well as middle base panel assembly 1320.

Additionally, as depicted in FIG. 1A, middle panel assembly 1300 caninclude first printhead management system substantially low particleenvironment, as well as a second printhead management system auxiliarypanel assembly (not shown). Various embodiments of an auxiliaryenclosure constructed as a section of a gas enclosure assembly can besealably isolated from the working volume of a gas enclosure system. Forvarious embodiments of systems and methods of the present teachings, anauxiliary enclosure can be less than or equal to about 1% of theenclosure volume of a gas enclosure system. In various embodiments ofsystems and methods of the present teachings, an auxiliary enclosure canbe can be less than or equal to about 2% of the enclosure volume of agas enclosure system. For various embodiments of systems and methods ofthe present teachings, an auxiliary enclosure can be less than or equalto about 5% of the enclosure volume of a gas enclosure system. Invarious embodiments of systems and methods of the present teachings, anauxiliary enclosure can be less than or equal to about 10% of theenclosure volume of a gas enclosure system. In various embodiments ofsystems and methods of the present teachings, an auxiliary enclosure canbe less than or equal to about 20% of the enclosure volume of a gasenclosure system. Should the opening of an auxiliary enclosure to anambient environment containing reactive gases be indicated forperforming, for example, a maintenance procedure, isolating an auxiliaryenclosure from the working volume of a gas enclosure can preventcontamination of the entire volume of a gas enclosure. Further, giventhe relatively small volume of an auxiliary enclosure in comparison tothe printing system enclosure portion of a gas enclosure, the recoverytime for an auxiliary enclosure can take significantly less time thanrecovery time for an entire printing system enclosure.

As depicted in FIG. 1B, gas enclosure assembly 1000 can include frontbase panel assembly 1220, middle base panel assembly 1320, and rear basepanel assembly 1420, which when fully-constructed form a contiguous baseor pan on which Printing system 2000 can be mounted. In a similarfashion as described for gas enclosure assembly 100 of FIG. 1A, thevarious frame members and panels comprising front panel assembly 1200,middle panel assembly 1300, and rear panel assembly 1400 of gasenclosure assembly 1000 can be joined around Printing system 2000 toform a printing system enclosure. Front panel assembly 1200 can becontoured around printing system 2000 mounted to form a first tunnelenclosure section of a gas enclosure. Similarly, rear panel assembly1400 can be contoured around printing system 2000 to form a secondtunnel enclosure section of a gas enclosure. Additionally, middle panelassembly 1300 can be contoured around a bridge section of a printingsystem 2000 to form a bridge enclosure section of a gas enclosure.Together, a first tunnel enclosure section, a second tunnel section anda bridge enclosure section can form a printing enclosure section. Aswill be discussed in more detail herein, according to the presentteachings, an auxiliary enclosure can be sealably isolated from aprinting system enclosure during, for example, a printing process forperforming various measurement and maintenance tasks, with little or nointerruption to the printing process.

Further, a fully constructed gas enclosure assembly, such as gasenclosure assembly 1000, when integrated with various environmentalcontrol systems can form various embodiments of a gas enclosure systemincluding various embodiments of an OLED printing system, such asPrinting system 2000. According to various embodiments of a gasenclosure system of the present teachings, environmental control of aninterior volume defined by a gas enclosure assembly can include controlof lighting, for example, by the number and placement of lights of aspecific wavelength, control of particulate matter using variousembodiments of a particle control system, control of reactive gasspecies using various embodiments of a gas purification system, andtemperature control of a gas enclosure assembly using variousembodiments of a thermal regulation system.

A printing system, such as printing system 2000 of FIG. 1B, shown inexpanded view in FIG. 1C, can be comprised of several devices andapparatuses, which allow the reliable placement of ink drops ontospecific locations on a substrate. These devices and apparatuses caninclude, but are not limited to, a printhead assembly, ink deliverysystem, a motion system for providing relative motion between aprinthead assembly and a substrate, substrate support apparatus,substrate loading and unloading system, and printhead management system.

A printhead assembly can include at least one inkjet head, with at leastone orifice capable of ejecting droplets of ink at a controlled rate,velocity, and size. The inkjet head is fed by an ink supply system whichprovides ink to the inkjet head. As shown in an expanded view of FIG.1C, Printing system 2000 can have a substrate, such as substrate 2050,which can be supported by a substrate support apparatus, such as achuck, for example, but not limited by, a vacuum chuck, a substratefloatation chuck having pressure ports, and a substrate floatation chuckhaving vacuum and pressure ports. In various embodiments of systems andmethods of the present teachings, a substrate support apparatus can be asubstrate floatation table. As will be discussed in more detailsubsequently herein, substrate floatation table 2200 of FIG. 1C can beused for supporting substrate 2050, and in conjunction with a Y-axismotion system, can be part of a substrate conveyance system providingfor the frictionless conveyance of substrate 2050. A Y-axis motionsystem of the present teachings can include first Y-axis support beam2351 and second Y-axis support beam 2352, which can include a grippersystem (not shown) for holding a substrate, as will be discussed in moredetail herein. Y-axis motion can be provided by either a linear airbearing or linear mechanical system. Substrate floatation table 2200 ofPrinting system 2000 shown in FIG. 1B and FIG. 1C can define the travelof substrate 2050 through gas enclosure assembly 1000 of FIG. 1A duringa printing process.

FIG. 1C illustrates generally an example of substrate floatation table2200 for a printing system 2000 that can include a floating conveyanceof a substrate, which can have a porous medium to provide floatation. Inthe example of FIG. 1C, a handler or other conveyance can be used toposition a substrate 2050 in an input region 2201 of a substratefloatation table 2200, such as located on a conveyor. The conveyer canposition the substrate 2050 at a specified location within the printingsystem such as using either mechanical contact (e.g., using an array ofpins, a tray, or a support frame configuration), or using gas cushion tocontrollably float the substrate 2050 (e.g., an “air bearing” tableconfiguration). A printing region 2202 of the substrate floatation table2200 can be used to controllably deposit one or more layers on thesubstrate 2050 during fabrication. The printing region 2202 can also becoupled to an output region 2203 of the substrate floatation table 2200.The conveyer can extend along the input region 2201, the printing region2202, and the output region 2203 of the substrate floatation table 2200,and the substrate 2050 can be repositioned as desired for variousdeposition tasks, or during a single deposition operation. Thecontrolled environments nearby the input region 2201, the printingregion 2202, and the output region 2203 can be commonly-shared.

The printing system 2000 of FIG. 1C can include one or more printheaddevices 2505, each printhead device having one or more printheads; e.g.nozzle printing, thermal jet or ink-jet type. The one or more printheaddevices 2505 can be coupled to or otherwise traversing an overheadcarriage, such as first X-axis carriage assembly 2301. For variousembodiments of printing system 2000 of the present teachings, one ormore printheads of one or more printhead devices 2505 can be configuredto deposit one or more patterned organic layers on the substrate 2050 ina “face up” configuration of the substrate 2050. Such layers can includeone or more of an electron injection or transport layer, a holeinjection or transport layer, a blocking layer, or an emission layer,for example. Such materials can provide one or more electricallyfunctional layers.

According to the floatation schemes shown in FIG. 1C, in an examplewhere the substrate 2050 is supported exclusively by the gas cushion, acombination of positive gas pressure and vacuum can be applied throughthe arrangement of ports or using a distributed porous medium. Such azone having both pressure and vacuum control can effectively provide afluidic spring between the conveyor and a substrate. A combination ofpositive pressure and vacuum control can provide a fluidic spring withbidirectional stiffness. The gap that exists between the substrate(e.g., substrate 2050) and a surface can be referred to as the “flyheight,” and such a height can be controlled or otherwise established bycontrolling the positive pressure and vacuum port states. In thismanner, the substrate Z-axis height can be carefully controlled in, forexample, the printing region 2202. In some embodiments, mechanicalretaining techniques, such as pins or a frame, can be used to restrictlateral translation of the substrate while the substrate is supported bythe gas cushion. Such retaining techniques can include using springloaded structures, such as to reduce the instantaneous forces incidentthe sides of the substrate while the substrate is being retained; thiscan be beneficial as a high force impact between a laterally translatingsubstrate and a retaining means can cause substrate chipping or evencatastrophic breakage.

Elsewhere, as illustrated generally in FIG. 1C, such as where the flyheight need not be controlled precisely, pressure-only floatation zonescan be provided, such as along the conveyor in the input or outputregions 2100 or 2300, or elsewhere. A “transition” zone can be providedsuch as where a ratio of pressure to vacuum nozzles increases ordecreases gradually. In an illustrative example, there can be anessentially uniform height between a pressure-vacuum zone, a transitionzone, and a pressure only zone, so that within tolerances, the threezones can lie essentially in one plane. A fly height of a substrate overpressure-only zones elsewhere can be greater than the fly height of asubstrate over a pressure-vacuum zone, such as in order to allow enoughheight so that a substrate will not collide with a floatation table inthe pressure-only zones. In an illustrative example, an OLED panelsubstrate can have a fly height of between about 150 micrometers (μ) toabout 300μ above pressure-only zones, and then between about 30μ toabout 50μ above a pressure-vacuum zone. In an illustrative example, oneor more portions of the substrate floatation table 2200 or otherfabrication apparatus can include an “air bearing” assembly provided byNewWay® Air Bearings (Aston, Pa., United States of America).

A porous medium can be used to establish a distributed pressurized gascushion for floating conveyance or support of the substrate 2050 duringone or more of printing, buffering, drying, or thermal treatment. Forexample, a porous medium “plate” such as coupled to or included as aportion of a conveyor can provide a “distributed” pressure to supportthe substrate 2050 in a manner similar to the use of individual gasports. The use of a distributed pressurized gas cushion without usinglarge gas port apertures can in some instances further improveuniformity and reduce or minimize the formation of mura or other visibledefects, such as in those instances where the use of relatively largegas ports to create a gas cushion leads to non-uniformity, in spite ofthe use of a gas cushion.

A porous medium can be obtained such as from Nano TEM Co., Ltd.(Niigata, Japan), such as having physical dimensions specified to occupyan entirety of the substrate 2050, or specified regions of the substratesuch as display regions or regions outside display regions. Such aporous medium can include a pore size specified to provide a desiredpressurized gas flow over a specified area, while reducing oreliminating mura or other visible defect formation.

Printing requires relative motion between the printhead assembly and thesubstrate. This can be accomplished with a motion system, typically agantry or split axis XYZ system. Either the printhead assembly can moveover a stationary substrate (gantry style), or both the printhead andsubstrate can move, in the case of a split axis configuration. Inanother embodiment, a printhead assembly can be substantiallystationary; for example, in the X and Y axes, and the substrate can movein the X and Y axes relative to the printheads, with Z axis motionprovided either by a substrate support apparatus or by a Z-axis motionsystem associated with a printhead assembly. As the printheads moverelative to the substrate, droplets of ink are ejected at the correcttime to be deposited in the desired location on a substrate. A substratecan be inserted and removed from the printer using a substrate loadingand unloading system. Depending on the printer configuration, this canbe accomplished with a mechanical conveyor, a substrate floatation tablewith a conveyance assembly, or a substrate transfer robot with endeffector. A printhead management system can be comprised of severalsubsystems which allow for such measurement tasks, such as the checkingfor nozzle firing, as well as the measurement of drop volume, velocityand trajectory from every nozzle in a printhead, and maintenance tasks,such as wiping or blotting the inkjet nozzle surface of excess ink,priming and purging a printhead by ejecting ink from an ink supplythrough the printhead and into a waste basin, and replacement ofprintheads. Given the variety of components that can comprise an OLEDprinting system, various embodiments of OLED printing system can have avariety of footprints and form factors.

With respect to FIG. 1C, printing system base 2100, can include firstriser 2120 and second riser 2122, upon which bridge 2130 is mounted. Forvarious embodiments of Printing system 2000, bridge 2130 can supportfirst X-axis carriage assembly 2301 and second X-axis carriage assembly2302, which can control the movement of first printhead assembly 2501and second printhead assembly 2502, respectively across bridge 2130. Forvarious embodiments of printing system 2000, first X-axis carriageassembly 2301 and second X-axis carriage assembly 2302 can utilize alinear air bearing motion system, which are intrinsically low-particlegenerating. According to various embodiments of a printing system of thepresent teachings, an X-axis carriage can have a Z-axis moving platemounted thereupon. In FIG. 1C, first X-axis carriage assembly 2301 isdepicted with first Z-axis moving plate 2310, while second X-axiscarriage assembly 2302 is depicted with second Z-axis moving plate 2312.Though FIG. 1C depicts two carriage assemblies and two printheadassemblies, for various embodiments of Printing system 2000, there canbe a single carriage assembly and a single printhead assembly. Forexample, either of first printhead assembly 2501 and second printheadassembly 2502 can be mounted on an X,Z-axis carriage assembly, while acamera system for inspecting features of substrate 2050 can be mountedon a second X,Z-axis carriage assembly. Various embodiments of Printingsystem 2000 can have a single printhead assembly, for example, either offirst printhead assembly 2501 and second printhead assembly 2502 can bemounted on an X,Z-axis carriage assembly, while a UV lamp for curing anencapsulation layer printed on substrate 2050 can be mounted on a secondX,Z-axis carriage assembly. For various embodiments of Printing system2000, there can be a single printhead assembly, for example, either offirst printhead assembly 2501 and second printhead assembly 2502,mounted on an X,Z-axis carriage assembly, while a heat source for curingan encapsulation layer printed on substrate 2050 can be mounted on asecond carriage assembly.

In FIG. 1C, each printhead assembly, such as first printhead assembly2501 and second printhead assembly 2502 of FIG. 1C, can have a pluralityof printheads mounted in at least one printhead device, as depicted inpartial view for first printhead assembly 2501, which depicts aplurality of printhead devices 2505. A printhead device can include, forexample, but not limited by, fluidic and electronic connections to atleast one printhead; each printhead having a plurality of nozzles ororifices capable of ejecting ink at a controlled rate, velocity andsize. For various embodiments of printing system 2000, a printheadassembly can include between about 1 to about 60 printhead devices,where each printhead device can have between about 1 to about 30printheads in each printhead device. A printhead, for example, anindustrial inkjet head, can have between about 16 to about 2048 nozzles,which can expel a droplet volume of between about 0.1 pL to about 200pL.

According to various embodiments of a gas enclosure system of thepresent teachings, given the sheer number of printhead devices andprintheads, first printhead management system 2701 and second printheadmanagement system 2702 can be housed in an auxiliary enclosure, whichcan be isolated from a printing system enclosure during a printingprocess for performing various measurement and maintenance tasks withlittle or no interruption to the printing process. As can be seen inFIG. 1C, first printhead assembly 2501 can be seen positioned relativeto first printhead management system 2701 for ready performance ofvarious measurement and maintenance procedures that can be performed byfirst printhead management system apparatuses 2707, 2709 and 2711.Apparatuses 2707, 2709, and 2011 can be any of a variety of subsystemsor modules for performing various printhead management functions. Forexample apparatuses 2707, 2709, and 2011 can be any of a dropmeasurement module, a printhead replacement module, a purge basinmodule, and a blotter module. As depicted in FIG. 1C, first printheadmanagement system 2701 can have apparatuses 2707, 2709 and 2711, whichcan be mounted on linear rail motion system 2705 for positioningrelative to first printhead assembly 2501. Similarly, variousapparatuses housed within second printhead management system 2702 can bemounted on linear rail motion system 2706 for positioning relative tofirst printhead assembly 2502.

With respect to various embodiments of a gas enclosure assembly havingan auxiliary enclosure that can be closed off from, as well as sealablyisolated from a first working volume, for example, a printing systemenclosure, reference is made again to FIG. 1B. As depicted in FIG. 1C,there can be four isolators on Printing system 2000; first isolator set2110 (second not shown on opposing side) and second isolator set 2112(second not shown on opposing side), which support substrate floatationtable 2200 of Printing system 2000. For gas enclosure assembly 1000 ofFIG. 1B, first isolator set 2110 and second isolator set 2112 can bemounted in each of a respective isolator well panel, such as firstisolator wall panel 1325 and second isolator wall panel 1327 of middlebase panel assembly 1320. For gas enclosure assembly 1000 of FIG. 1B,middle base assembly 1320 can include first printhead management systemauxiliary panel assembly 1330, as well as second printhead managementsystem auxiliary panel assembly 1370. FIG. 1B of gas enclosure assembly1000 depicts first printhead management system auxiliary panel assembly1330 that can include first back wall panel assembly 1338. Similarly,also depicted is second printhead management system auxiliary panelassembly 1370 that can include second back wall panel assembly 1378.First back wall panel assembly 1338 of first printhead management systemauxiliary panel assembly 1330 can be constructed in a similar fashion asshown for second back wall panel assembly 1378. Second back wall panelassembly 1378 of second printhead management system auxiliary panelassembly 1370 can be constructed from second back wall frame assembly1378 having second seal-support panel 1375 sealably mounted to secondback wall frame assembly 1378. Second seal-support panel 1375 can havesecond passage 1365, which is proximal to a second end of base 2100 (notshown). Second seal 1367 can be mounted on second seal-support panel1375 around second passage 1365. A first seal can be similarlypositioned and mounted around a first passage for first printheadmanagement system auxiliary panel assembly 1330. Each passage inauxiliary panel assembly 1330 and auxiliary panel assembly 1370 canaccommodate a printhead management system platform, such as first andsecond printhead management system platforms 2703 and 2704 of FIG. 1Cpass through the passages. According to the present teachings, in orderto sealably isolate auxiliary panel assembly 1330 and auxiliary panelassembly 1370 the passages, such as second passage 1365 of FIG. 1B mustbe sealable. It is contemplated that various seals, such as aninflatable seal, a bellows seal and a lip seal can be used for sealing apassage, such as second passage 1365 of FIG. 1B, around a printheadmanagement system platform affixed to a printing system base.

First printhead management system auxiliary panel assembly 1330 andsecond printhead management system auxiliary panel assembly 1370 caninclude first printhead assembly opening 1342 of first floor panelassembly 1341 and second printhead assembly opening 1382 of second floorpanel assembly 1381; respectively. First floor panel assembly 1341 isdepicted in FIG. 1B as part of first middle enclosure panel assembly1340 of middle panel assembly 1300. First floor panel assembly 1341 is apanel assembly in common with both first middle enclosure panel assembly1340 and first printhead management system auxiliary panel assembly1330. Second floor panel assembly 1381 is depicted in FIG. 1B as part ofsecond middle enclosure panel assembly 1380 of middle panel assembly1300. Second floor panel assembly 1381 is a panel assembly in commonwith both second middle enclosure panel assembly 1380 and secondprinthead management system auxiliary panel assembly 1370.

As previously discussed herein, first printhead assembly 2501 can behoused in first printhead assembly enclosure 2503, and second printheadassembly 2502 can be housed in second printhead assembly enclosure 2504.According to systems and methods of the present teachings, firstprinthead assembly enclosure 2503 and second printhead assemblyenclosure 2504 can have an opening at the bottom that can have a rim(not shown), so that various printhead assemblies can be positioned forprinting during a printing process. Additionally, the portions of firstprinthead assembly enclosure 2503 and second printhead assemblyenclosure 2504 forming a housing can be constructed as previouslydescribed for various panel assemblies, so that the frame assemblymembers and panels are capable of providing an hermetically-sealedenclosure.

A compressible gasket which can additionally be used for the hermeticsealing of various frame members, can be affixed around each of firstprinthead assembly opening 1342 and second printhead assembly opening1382, or alternatively around the rim of first printhead assemblyenclosure 2503 and second printhead assembly enclosure 2504.

According to the present teachings, compressible gasket material can beselected from, for example, but not limited by, any in the class ofclosed-cell polymeric materials, also referred to in the art as expandedrubber materials or expanded polymer materials. Briefly, a closed-cellpolymer is prepared in a fashion whereby gas is enclosed in discretecells; where each discrete cell is enclosed by the polymeric material.Properties of compressible closed-cell polymeric gasket materials thatare desirable for use in gas-tight sealing of frame and panel componentsinclude, but are not limited by, that they are robust to chemical attackover a wide range of chemical species, possess excellentmoisture-barrier properties, are resilient over a broad temperaturerange, and they are resistant to a permanent compression set. Ingeneral, compared to open-cell-structured polymeric materials,closed-cell polymeric materials have higher dimensional stability, lowermoisture absorption coefficients, and higher strength. Various types ofpolymeric materials from which closed-cell polymeric materials can bemade include, for example, but not limited by, silicone, neoprene,ethylene-propylene-diene terpolymer (EPT); polymers and composites madeusing ethylene-propylene-diene-monomer (EPDM), vinyl nitrile,styrene-butadiene rubber (SBR), and various copolymers and blendsthereof.

In addition to close-cell compressible gasket materials, another exampleof a class of compressible gasket material having desired attributes foruse in constructing embodiments of a gas enclosure assembly according tothe present teachings includes the class of hollow-extruded compressiblegasket materials. Hollow-extruded gasket materials as a class ofmaterials have the desirable attributes, including, but not limited by,that they are robust to chemical attack over a wide range of chemicalspecies, possess excellent moisture-barrier properties, are resilientover a broad temperature range, and they are resistant to a permanentcompression set. Such hollow-extruded compressible gasket materials cancome in a wide variety of form factors, such as for example, but notlimited by, U-cell, D-cell, square-cell, rectangular-cell, as well asany of a variety of custom form factor hollow-extruded gasket materials.Various hollow-extruded gasket materials can be fabricated frompolymeric materials that are used for closed-cell compressible gasketfabrication. For example, but not limited by, various embodiments ofhollow-extruded gaskets can be fabricated from silicone, neoprene,ethylene-propylene-diene terpolymer (EPT); polymers and composites madeusing ethylene-propylene-diene-monomer (EPDM), vinyl nitrile,styrene-butadiene rubber (SBR), and various copolymers and blendsthereof. Compression of such hollow cell gasket materials should notexceed about 50% deflection in order to maintain the desired attributes.It is contemplated that various types of inflatable seals can beutilized for sealing a printhead assembly using first printhead assemblydocking gasket 1345 and second printhead assembly docking gasket 1385.Such inflatable seals may provide rapid sealing and unsealing duringprocessing, as well as being fabricated from low-contaminationmaterials, such as low particle generating, low outgassing polymericmaterials, such as silicones, neoprenes and butyl rubber materials.

As depicted in FIG. 1B, first printhead assembly docking gasket 1345 andsecond printhead assembly docking gasket 1385 can be affixed aroundfirst printhead assembly opening 1342 and second printhead assemblyopening 1382, respectively. During various printhead measurement andmaintenance procedures, first printhead assembly 2501 and secondprinthead assembly 2502 can be positioned by first X,Z-axis carriageassembly 2301 and second X,Z-axis carriage assembly 2302, respectively,over first printhead assembly opening 1342 of first floor panel assembly1341 and second printhead assembly opening 1382 of second floor panelassembly 1381, respectively. In that regard, for various printheadmeasurement and maintenance procedures, first printhead assembly 2501and second printhead assembly 2502 can be positioned over firstprinthead assembly opening 1342 of first floor panel assembly 1341 andsecond printhead assembly opening 1382 of second floor panel assembly1381, respectively, without covering or sealing first printhead assemblyopening 1342 and second printhead assembly opening 1382. First X,Z-axiscarriage assembly 2301 and second X,Z-axis carriage assembly 2302 candock first printhead assembly enclosure 2503 and second printheadassembly enclosure 2504, respectively, with first printhead managementsystem auxiliary panel assembly 1330 and second printhead managementsystem auxiliary panel assembly 1370, respectively. In various printheadmeasurement and maintenance procedures, such docking may effectivelyclose first printhead assembly opening 1342 and second printheadassembly opening 1382 without the need for sealing first printheadassembly opening 1342 and second printhead assembly opening 1382. Forvarious printhead measurement and maintenance procedures, the dockingcan include the formation of a gasket seal between each of the printheadassembly enclosures and the printhead management system panelassemblies. In conjunction with sealably closing passages, such assecond passage 1365 and a complementary first passage of FIG. 1B, whenfirst printhead assembly enclosure 2503 and second printhead assemblyenclosure 2504 are docked with first printhead management systemauxiliary panel assembly 1330 and second printhead management systemauxiliary panel assembly 1370 to sealably close first printhead assemblyopening 1342 and second printhead assembly opening 1382, the combinedstructures so formed are hermetically sealed.

Additionally, according to the present teachings, an auxiliary enclosurecan be isolated from, for example, another interior enclosure volume,such as the printing system enclosure, as well as the exterior of a gasenclosure assembly, by using a structural closure to sealably close apassageway, such as first printhead assembly opening 1342 and secondprinthead assembly opening 1382 of FIG. 1B. According to the presentteachings, a structural closure can include a variety of sealablecoverings for an opening or passageway; such opening or passagewayincluding non-limiting examples of an enclosure panel opening orpassageway. According to systems and methods of the present teachings, agate can be any structural closure that can be used to reversibly coveror reversibly sealably close any opening or passageway using pneumatic,hydraulic, electrical, or manual actuation. As such, first printheadassembly opening 1342 and second printhead assembly opening 1382 of FIG.1B can be reversibly covered or reversibly sealably closed using a gate.

In the expanded view of Printing system 2000 of FIG. 1C, variousembodiments of a printing system can include substrate floatation table2200, supported by substrate floatation table base 2220. Substratefloatation table base 2220 can be mounted on printing system base 2100.Substrate floatation table 2200 of OLED printing system can supportsubstrate 2050, as well as defining the travel over which substrate 2050can be moved through gas enclosure assembly 1000 during the printing ofan OLED substrate. A Y-axis motion system of the present teachings caninclude first Y-axis support beam 2351 and second Y-axis support beam2352, which can include a gripper system (not shown) for holding asubstrate, which will be discussed in more detail herein. Y-axis motioncan be provided by either a linear air bearing or linear mechanicalsystem. In that regard, in conjunction with a motion system; as depictedin FIG. 1C, a Y-axis motion system, substrate floatation table 2200 canprovide frictionless conveyance of substrate 2050 through a printingsystem.

FIG. 1D depicts an expanded view of first printhead management system2701 housed within first printhead management system auxiliary panelassembly 1330 in accordance with various embodiments of a gas enclosureassembly and system of the present teachings. As depicted in FIG. 1D,auxiliary panel assembly 1330 is shown as a cut-away view to moreclearly see the details of first printhead management system 2701.Various embodiments of a printhead management system according to thepresent teachings, such as first printhead management system 2701 ofFIG. 1D, apparatuses 2707, 2709, and 2011 can be a variety of subsystemsor modules for performing various functions. For example apparatuses2707, 2709, and 2011 can be a drop measurement module, a printhead purgebasin module and a blotter module. As depicted in FIG. 1D, printheadreplacement module 2713 can provide locations for docking at least oneprinthead device 2505. In various embodiments of first printheadmanagement system 2701, first printhead management system auxiliarypanel assembly 1330 can be maintained to the same environmentalspecifications that gas enclosure assembly 1000 (see FIG. 1A) ismaintained. First printhead management system auxiliary panel assembly1330 can have handler 2530 positioned for the carrying out tasksassociated with various printhead management procedures. For example,each subsystem can have various parts that are consumable by nature, andrequire replacement, such as replacing blotter paper, ink, and wastereservoirs. Various consumable parts can be packaged for readyinsertion, for example, in a fully automated mode using a handler. As anon-limiting example, blotter paper can be packaged in a cartridgeformat, which can be readily inserted for use into a blotting module. Byway of another non-limiting example ink can be packaged in a replaceablereservoir, as well as a cartridge format for use in a printing system.Various embodiments of a waste reservoir can be packaged in a cartridgeformat, which can be readily inserted for use into a purge basin module.Additionally, parts of various components of a printing system subjectto on-going use can require periodic replacement. During a printingprocess, expedient management of a printhead assembly, for example, butnot limited by, an exchange of a printhead device or printhead, can bedesirable. A printhead replacement module can have parts, such as aprinthead device or printhead, which can be readily inserted for useinto a printhead assembly. A drop measurement module used for checkingfor nozzle firing, as well as the measurement based on optical detectionof drop volume, velocity and trajectory from every nozzle can have asource and a detector, which can require periodic replacement after use.Various consumable and high-usage parts can be packaged for readyinsertion, for example, in a fully automated mode using a handler.Handler 2530 can have end effector 2536 mounted to arm 2534. Variousembodiments of an end effector configuration can be used, for example, ablade-type end effector, a clamp-type end effector, and a gripper-typeend effector. Various embodiments of an end effector can includemechanical grasping and clamping, as well as pneumatic orvacuum-assisted assemblies to either actuate portions of the endeffector or otherwise retain a printhead device or a printhead from aprinthead device.

Regarding the replacement of a printhead device or printhead, printheadreplacement module 2713 of printhead management system 2701 FIG. 1D caninclude a docking station for a printhead device having at least oneprinthead, as well as a storage receptacle for a printhead. As eachprinthead assembly (see FIG. 1B) can include between about 1 to about 60printhead devices, and as each printhead device can have between about 1to about 30 printheads, then various embodiments of a printing system ofthe present teachings can have between about 1 to about 1800 printheads.In various embodiments of printhead replacement module 2713, while aprinthead device is docked, each printhead mounted to the printheaddevice can be maintained in an operable condition while not in use in aprinting system. For example, when placed in a docking station, eachprinthead on each printhead device can be connected to an ink supply andan electrical connection. Electrical power can be provided to eachprinthead on each printhead device, so that a periodic firing pulse toeach nozzle of each printhead can be applied while docked in order toensure that the nozzles remain primed and do not clog. Handler 2530 ofFIG. 1D can be positioned proximal to printhead assembly 2500. Printheadassembly 2500 can be docked over first printhead management systemauxiliary panel assembly 1330, as depicted in FIG. 1D. During aprocedure for exchanging a printhead, handler 2530 can remove a targetpart; either a printhead or printhead device having at least oneprinthead, from printhead assembly 2500. Handler 2530 can retrieve areplacement part, such as a printhead device or a printhead, fromprinthead replacement module 2713, and complete the replacement process.The removed part can be placed in printhead replacement module 2713 forretrieval.

In FIG. 2A, gas enclosure system 500 can have first tunnel enclosuresection 1200, which can have inlet gate 1242 for receiving a substrate,bridge enclosure section 1300, and second tunnel enclosure section 1400,which together can form a printing system enclosure. Additionally, gasenclosure system 500 can have auxiliary enclosure 1330. Auxiliaryenclosure 1330 can be sealably isolated from the printing systemenclosure of gas enclosure system 500. For example, during a printingprocess, auxiliary enclosure 1330 can be sealably isolated from theprinting system enclosure of gas enclosure system 500 for performingvarious measurement and maintenance tasks, with little or nointerruption to the printing process. As will be discussed in moredetail subsequently herein in discussion of FIG. 8, purified inert gasfrom a purification system, such as purification system 3130 of FIG. 8,can circulate into a printing system enclosure of gas enclosure system500, as well as auxiliary enclosure 1300.

For various embodiments of a printing system of the present teachings, aprinthead assembly can include between about 1 to about 60 printheaddevices. Recalling, a printhead device can include, for example, but notlimited by, fluidic and electronic connections to at least oneprinthead; each printhead having a plurality of nozzles or orificescapable of ejecting ink at a controlled rate, velocity and size, whereeach printhead device can have between about 1 to about 30 printheads ineach printhead device. A printhead, for example, an industrial inkjethead, can have between about 16 to about 2048 nozzles, which can expel adroplet volume of between about 0.1 pL to about 200 pL. Given the sheernumber of printhead devices and printheads, an auxiliary enclosure canhouse various embodiments of a printhead management system. According tothe present teachings, an auxiliary enclosure can be isolated from aprinting system enclosure during a printing process for performingvarious measurement and maintenance tasks, for example, but not limitedby, using various devices and apparatuses of a printhead managementsystem. As such, various measurement and maintenance tasks can beperformed with little or no interruption to the printing process.

FIG. 2B depicts a perspective view of auxiliary enclosure 1330 of a gasenclosure system according to various embodiments of the presentteachings. Auxiliary enclosure 1330 can be an embodiment of an auxiliaryenclosure that can be utilized with, for example, but not limited by,various gas enclosure systems of the present teachings, such as gasenclosure system 1000 of FIG. 1A and gas enclosure system 500 of FIG.2A. As shown in FIG. 2B, auxiliary enclosure 1330 can have printheadmanagement system platform 2703, which can have linear rail system 2705for positioning various devices and apparatuses used for variousmeasurement and maintenance procedures relative to various printheaddevices of a printhead assembly. For example, in the partially explodedview of FIG. 2B, printhead assembly 2500 is shown positioned overprinthead assembly opening 1350. Printhead assembly 2500 can have aplurality of printhead devices, such as 2505A, 2505B, and 2505C, shownin FIG. 2C. First motion system platform 2800A and second motion systemplatform 2800B can be used to position various devices and apparatusesused for various measurement and maintenance procedures mounted on themotion system platforms relative to each of the plurality of printheaddevices of printhead assembly 2500.

The partially exploded view of FIG. 2C depicts a top perspective view ofprinthead management system 2700 in relationship to printhead assembly2500. As depicted in FIG. 2C, first motion system platform 2800A andsecond motion system platform 2800B can be moved along a Y-axisdirection on linear rail system 2705. In that fashion, linear railsystem 2705 can position various devices and apparatuses mounted on themotion system platforms relative to each of printhead devices 2505A,2505B, and 2505C of printhead assembly 2500. First motion systemplatform 2800A can support first X-axis motion system platform 2810A,which can have first X-axis linear rail system 2820A. First X-axislinear rail system 2820A can move various apparatuses mounted upon firstX-axis motion system platform 2810A in a direction orthogonal to thedirection of first motion system platform 2800A on linear rail system2705. Similarly, second motion system platform 2800B can support secondX-axis motion system platform 2810B, which can have second X-axis linearrail system 2820B. Second X-axis linear rail system 2820B can movevarious apparatuses mounted upon second X-axis motion system platform2810B in a direction orthogonal to the direction of second motion systemplatform 2800B on linear rail system 2705. In that regard, the X,Ymotion of first motion system platform 2800A and first X-axis motionsystem platform 2810A, as well as the X,Y motion of second motion systemplatform 2800B and second X-axis motion system platform 2810B canprovide accurate X,Y positioning of various devices and apparatusesrelative to each of printhead devices 2505A, 2505B, and 2505C.

As depicted in FIG. 2C, various devices mounted on first X-axis motionsystem platform 2810A of first motion system platform 2800A can includepurge basins 2707A, 2707B and 2707C for each of printhead device 2505A,2505B, and 2505C, as well as blotting station 2709. Depicted in FIG. 2Cfor providing calibration information are first drop measurement module2711A, mounted on first X-axis motion system platform 2810A of firstmotion system platform 2800A and second drop measurement module 2711B,mounted on second X-axis motion system platform 2810B of second motionsystem platform 2800B. First drop measurement system 2711A can be basedon, for example, but not limited by, printing drops from each nozzle ofeach printhead of each printhead device on a film under specifiedconditions, and then imaging the film. Information such as drop volume,speed and trajectory can be obtained through image analysis of data soobtained. Alternatively, second drop measurement system 2711B can bebased on, for example, but not limited by, and optical measurementsystem. For example, drop volume, velocity and trajectory for each dropfrom each nozzle of each printhead of each printhead device can bedetermined using a laser light scattering technique, such as phaseDoppler analysis (PDA) and phase Doppler interferometry (PDI).

FIG. 3 depicts a Y-axis motion system according to the presentteachings, depicted in FIG. 3 as mounted upon Y-axis beam 2350, whichcan be, for example, a granite beam. As depicted in the coordinatesystem, a substrate, such as 2050, which is mounted on floatation table2200, can travel in a +/−Y-axis direction. Floatation table 2200provides frictionless, low-particle generating substrate support ofsubstrate 2050 with precision Z-axis fly height, while Y-axis motionsystem 2600 provides frictionless, low-particle Y-axis conveyance ofsubstrate 2050 relative to a printhead assembly, such as printheadassembly 2501 of FIG. 1C.

Various embodiments of low-particle generating Y-axis motion systems ofthe present teachings utilized in conjunction with a floatation tablecan be compared to, for example, a chuck mounted on a large turntable.In the case of a chuck mounted on a large turntable, large motors wouldbe required in the operation of the large turntable, which would resultin significant heat dissipation, as well as particle generation due tothe movement of solid parts against solid parts. In the case of variousembodiments of a gripper system of the present teachings, the onlyinertia in the system is the mass of a substrate and the gripperassembly, so that any linear motor required for Y-axis movement issubstantially smaller than for a chuck mounted on a turntable.

Moreover, the inventors have discovered that Y-axis beam 2350, eventhough manufactured to provide surfaces that are both flat and parallelto a high degree, may produce excursions in travel that may beunacceptable for the intended use for the precision of orientation of asubstrate with respect to the theta-Z (θ-Z) axis during Y-axis travel.For example, but not limited by, printing an ink into a pixel of an OLEDdevice substrate is a process requiring precision orientation of asubstrate in the axis of travel for which a beam manufactured to hightolerances of flatness and parallelism may still produce unacceptableexcursions in substrate orientation during travel. As such, variousembodiments of a Y-axis motion system 2600 of the present teachingsutilizing an air bearing motion system for conveying Y-axis carriageassembly 2620 can provide reliable, accurate low-particle generatingY-axis conveyance of a substrate, providing operation at high speed withfast acceleration and deceleration, as well as obviating the need fordissipation of excess heat contamination in a gas enclosure system.Additionally, gripper motion control assembly 2650 of Y-axis motionsystem 2600 can provide dynamic rotation of the orientation of asubstrate about the theta-Z (θ-Z) axis during Y-axis travel to maintaina high degree of precision for substrate orientation parallel to theaxis of travel. Accordingly, gripper motion control assembly 2650 ofY-axis motion system 2600 can maintain substrate orientation with a highdegree of precision parallel to the Y-axis direction of travel in ahorizontal plane determined, for example, by the fly height of asubstrate.

As shown in FIG. 3, various embodiments of linear Y-axis motion system2600 can include substrate gripper assembly 2610, Y-axis carriageassembly 2620, as well as gripper motion control assembly 2650. In FIG.3, gripper assembly 2610, can include a substrate gripping surface, forexample, but not limited by, such as vacuum chuck bar 2612, which can besupported on substrate gripper frame 2614. Substrate gripper frame 2614can be mounted to Y-axis carriage assembly 2620 of a Y-axis motionsystem assembly 2600. In FIG. 3, first air-bearing puck 2628A and secondair-bearing puck 2628B of Y-axis carriage assembly 2620 are indicatedmounted to first saddle arm 2622A and second saddle arm 2622B,respectively, which are part of a plurality of air-bearings supportingY-axis carriage assembly 2620. Y-axis carriage assembly 2620 can betranslated in a +/−Y-axis direction using a brushless linear motor. Aswill be discussed in more detail subsequently herein, gripper motioncontrol assembly 2650 can utilize a dual voice coil motor assembly, suchas voice coil motor assemblies, 2630A and 2630B, as well as pivotassembly 2660. Various embodiments of a gripper motion control assemblycan include at least one voice coil motor and air bushing center pivotin conjunction with a position sensor and motion controller. Variousembodiments of a Y-axis motion system of the present teachings based onvoice coil motors are highly reliable, and can provide orientationaccuracies of less than one micron. Additionally, the direct coupling ofthe substrate to such a gripper assembly of a Y-axis motion systemallows for frictionless high speed operation with fast acceleration, aswell as fast deceleration, using a linear brushless motor for theconveyance of Y-axis carriage assembly 2620, as well as dynamic rotationof the orientation of a substrate about the theta-Z (θ-Z) axis duringY-axis travel using gripper motion control assembly 2650 to maintain ahigh degree of precision for substrate orientation parallel to the axisof travel. As such, various embodiments of a Y-axis motion systemutilizing an air-bearing gripper system can provide precisionlow-particle generating conveyance of substrate 2050 supported onfloatation table 2200 through a printing system, such as printing system2000 of FIG. 1C. Such a frictionless Y-axis motion system for moving asubstrate can utilize either one or two Y-axis rails. Service bundlecarrier 2430 can be used for the management of various service bundles,which can include, for example, but not limited by optical cables,electrical cables, wires, tubing and the like. Various embodiments ofservice bundles according to the present teachings can be connected to aprinting system to provide various optical, electrical, mechanical andfluidic connections required to operate a functioning printing system.

FIG. 4A is a top view of Y-axis motion system 2600, showing gripperassembly 2610, Y-axis carriage assembly top plate 2624, and grippermotion control assembly 2650. Gripper assembly 2610 can include vacuumchuck bar 2612, mounted on gripper frame 2614. Y-axis carriage assemblytop plate 2624 is depicted in FIG. 4A having first end 2623 and secondend 2625. Gripper assembly 2610 and Y-axis carriage assembly 2620 can beadjoined through the subassemblies of gripper motion control assembly2650. For example, first voice coil assembly 2630A and second voice coilassembly 2630B have first and second voice coil housing 2632A and 2623B,respectively, which can be secured to Y-axis carriage assembly 2620 onone side of the voice coil assembly housing and to gripper assembly 2610on the opposing side of the voice coil housing. Additionally, centerpivot 2660 can include air bearing housing 2662, which can be secured toboss 2616 of gripper assembly 2610. FIG. 4B is a partial top view ofair-bearing Y-axis motion system 2600 of FIG. 4A, depicting an expandedtop view of second end 2625 of Y-axis motion system 2600. In FIG. 4B, anexpanded top view of gripper assembly 2610, as well as an expanded topview of voice coil assembly 2630B are particularly apparent. Variousembodiments of vacuum chuck bar 2612 mounted on gripper frame 2614 caninclude a plurality of vacuum sockets 2613, of which three of theplurality are indicated in FIG. 4B. Vacuum sockets 2613 are spaced atintervals along the length of vacuum chuck bar 2612, so that vacuumchuck bar 2612 can readily engage and release a substrate obviating theneed for two-sided mechanical gripping of a substrate, such as that of a2-fingered or 3-fingered gripping device. In addition to firstair-bearing puck 2628A and second air-bearing puck 2628B of FIG. 3 forsupporting Y-axis carriage assembly 2620, second upper puck 2628D can bemounted to the underside of Y-axis carriage assembly top plate 2624 (seeFIG. 3 and FIG. 4B). A first upper puck (not shown) can be mountedsymmetrically under the opposing first end 2623 of Y-axis carriageassembly top plate 2624 proximal to first saddle arm 2622A (see FIG.4A).

As will be discussed in more detail herein, in addition to air-bearingpucks for supporting Y-axis carriage assembly 2620, voice coilair-bearing 2641 of second voice coil assembly 2630B depicted in FIG.4B, along with a voice coil air-bearing (not shown) associated withfirst voice coil assembly 2630A (see FIG. 4A) can be utilized for thevertical stabilization of gripper assembly 2610. In the top viewrendering of FIG. 4B, a single air bearing is visible. As a preload of avoice coil air-bearing in voice coil assembly, such as voice coilassembly 2630A and 2630B of FIG. 4A can ensure a requisite systemstiffness. As depicted in the top view of FIG. 4B, various embodimentsof a Y-axis motion system of the present teaching can include a singleair bearing. Various embodiments of systems and methods utilizing asingle air bearing in a voice coil assembly can preload the air bearingusing, for example, but not limited by, gravity, vacuum or magneticpreload. Various embodiments of a Y-axis motion system may utilize anopposing second air bearing to provide bearing preload. Variousembodiments of a voice coil motor assembly of the present teachings,such voice coil assembly 2630B of FIG. 4B, can include voice coilhousing 2633B that can be adjoined to Y-axis carriage 2620. As will bediscussed in more detail herein, voice coil gripper frame mounting block2648B of voice coil assembly 2630B can be used to affix a voice coilassembly to gripper frame 2614. Voice coil assembly 2630B can alsoinclude voice coil shaft 2634B, which can have pivot screw 2635B andholding screw 2636B, as well as set screw 2637B. Additionally, voicecoil assembly 2630B can have linear encoder 2638B. Finally, center pivot2660 is an air-bushing that is configured to provide an axis of rotationfor reliable and accurate theta-Z (θ-Z) rotation for embodiments ofgripper motion control system 2650 of the present teachings. Though theparts of voice coil assembly 2630B have been described, voice coilassembly 2630A can be similarly described.

FIG. 5A is an isometric view of a carriage assembly, gripper motioncontrol assembly, and gripper assembly of a Y-axis motion systemaccording to various embodiments of systems and methods of the presentteachings. As depicted in FIG. 5A FIG. 5A depicts Y-axis carriageassembly 2620 with first and second saddle arms 2622A and 2622B,respectively; the saddle arms having first puck 2628A and second puck2628B mounted thereupon, respectively; so that the pucks are proximal toY-axis beam 2350 (see FIG. 3). First and second saddle arms 2622A and2622B, as well as Y-axis carriage assembly side frame 2626 can be joinedto Y-axis carriage assembly top plate 2624. Y-axis carriage assemblyside frame 2626 can have first side 2627, which is proximal to Y-axisbeam 2350 (see FIG. 3), and second side 2629, which is proximal togripper frame 2614. Gripper motion control assembly 2650 can includefirst and second voice coil assemblies, 2630A and 2630B, respectively,as well as center pivot assembly 2660. As previously discussed herein,gripper motion control assembly 2650 is adjoined to both the Y-axiscarriage assembly 2620 and the gripper assembly 2610; effectivelyadjoining the Y-axis carriage assembly and gripper assembly thereby (seealso FIG. 4B). As a substrate, such as substrate 2050 of FIG. 3, is heldby vacuum chuck bar 2612 mounted to gripper frame 2614, dynamic angular(θ-Z) adjustment to offset the effects of imperfections in a Y-axis beamcan be done for a substrate by gripper motion control assembly 2650 asY-axis carriage assembly 2620 travels over Y-axis beam 2350 (see FIG.3). Accordingly, a substrate during Y-axis travel can be maintained withhigh precision with respect the orientation of a substrate about thetheta-Z (θ-Z) axis during Y-axis travel using gripper motion controlassembly 2650 to maintain a high degree of precision for substrateorientation parallel to the axis of travel. Various embodiments ofgripper motion control assembly 2650 can maintain the orientation of asubstrate parallel to the Y-axis of travel to within +/−4300microradians. Accordingly, gripper motion control assembly 2650 ofY-axis motion system 2600 can maintain substrate orientation with a highdegree of precision parallel to the Y-axis direction of travel in ahorizontal plane determined, for example, by the fly height of asubstrate.

FIG. 5B depicts a long section perspective view through Y-axis carriageassembly 2620 of FIG. 5A, which illustrates generally gripper assembly2610 mounted to Y-axis carriage assembly 2620. In FIG. 5B, first andsecond voice coil motor assemblies, 2630A and 2630B, respectively, aswell as vacuum chuck bar 2612 on gripper frame 2614, and center pivot2660 are indicated. In FIG. 3 and FIG. 5A, first air-bearing puck 2628Aand second air-bearing puck 2628B of Y-axis carriage assembly 2620 areindicated. In FIG. 4B, a first and second air-bearing puck under Y-axiscarriage assembly top plate 2624 were described. As shown in FIG. 5B,Y-axis carriage assembly side frame 2626 can have a plurality ofair-bearing pucks mounted thereupon, such as air-bearing pucks 2628Ethrough 2640H. In addition to the air bearing pucks located on thesaddle arms and top plate of a carriage assembly proximal to Y-axis beam2350, a plurality of air-bearing pucks mounted on Y-axis carriageassembly side frame 2626 can provide bearing support between side frame2626 and the corresponding side of Y-axis beam 2350. Various embodimentsof a Y-axis motion system of the present teaching, for example, asgenerally illustrated in FIG. 3 through FIG. 5B can provide for alow-particle generating, low heat-generating conveyance of substratethrough a printing system.

FIG. 6 depicts the second side 2627 of Y-axis carriage assembly sideframe 2626, which is the side proximal to gripper frame 2614, andillustrates generally a Y-axis moving system subassembly includinggripper motion control assembly 2650 without gripper frame 2614 mounted.First and second voice coil assemblies 2630A and 2630B can be mounted atopposing top ends of second side 2627 of Y-axis carriage assembly sideframe 2626, while center pivot 2660 can be mounted in the top centerportion of second side 2627 of Y-axis carriage assembly side frame 2626.First and second voice coil assemblies 2630A and 2630B can include firstvoice coil assembly shaft 2634A and second voice coil assembly shaft2634B, respectively, as well as first voice coil assembly housing 2632Aand second voice coil assembly housing 2632B. Each of first voice coilassembly shaft 2634A and second voice coil assembly shaft 2634B can havea set screw; first voice coil assembly set screw 2635A and second voicecoil assembly set screw 2637B, respectfully, each set screw having ashank extending into voice coil assembly set screw hole 2621A and 2621B,respectively. Additionally, as depicted in FIG. 6, each voice coilassembly shaft; first voice coil assembly shaft 2634A and second voicecoil assembly shaft 2634B can have a pivot screw and a holding screw;pivot screw 2635A and holding screw 2636A for first voice coil assemblyshaft 2634A and pivot screw 2635B and holding screw 2636B for firstvoice coil assembly shaft 2634B. For the initial adjustment of thehorizontal position of a gripper assembly and substrate relative to afloatation table, for both first and second voice coil assemblies 2630Aand 2630B, the pivot screw and holding screw can be loosened, until thehorizontal position of gripper assembly and substrate are correctlyadjusted, and then the pivot screw and holding screw are tightened.Adjusting voice coil assemblies 2630A and 2630B equally can be done tomake an adjustment in a gripper assembly's position in +/−Z relative toa floatation table (see FIG. 3), while adjusting voice coil assemblies2630A and 2630B unequally can be done to make an adjustment in a gripperassembly's position in theta-X (θ-X) relative to a floatation table (seeFIG. 3). As previously discussed herein, various embodiments of voicecoil assemblies of the present teachings utilize a pair of air bearings,which an upper or top air bearing, such as air bearing 2640A of firstvoice coil assembly 2630A and air bearing 2641A of second voice coilassembly 2630B, as well as an opposing bottom air bearing, such as airbearing 2640B of first voice coil assembly 2630A and air bearing 2641Bof second voice coil assembly 2630B. Each bottom air bearing is used topreload each upper or top air bearing.

FIG. 7A illustrates generally an isometric view of a voice coil assemblyaccording to the present teachings. A voice coil assembly can include avoice coil housing 2632, which can have first voice coil housing sidefirst 2631 and opposing voice coil housing second side 2633, as well asvoice coil shaft 2634. Voice coil shaft 2634 can include pivot screw2635 and holding screw 2636, as well as set screw 2637, all of which canbe used in the initial vertical adjustment of the of a gripper assemblyrelative to a flotation table, as previously discussed herein withrespect to FIG. 6. In FIG. 7B, pivot screw 2635 and holding screw 2636have been removed, so that pivot through hole 2645, which accommodatespivot screw 2635, and through slot 2646, which accommodates holdingscrew 2636, are apparent. Voice coil assembly 2630 can have a pair ofair bearings such as upper air bearing 2642A and opposing or lower airbearing 2642B, for which the lower air bearing is used to preload theupper air bearing. Voice coil assembly 2630 can include voice coilgripper frame mounting block 2648, which can be used to affix a voicecoil assembly to a gripper frame (see FIG. 4B). Additionally, a voicecoil assembly of the present teachings can include liner encoder 2638,which is oriented in the X direction. Various embodiments of a Y-axismotion system of the present teachings utilize a linear encoder headthat allows the voice coils to be oriented within 1-2 microns in the Xdirection relative to a carriage assembly, providing for dynamicadjustment in theta-Z (θ-Z) during the conveyance of a substrate on aY-axis beam utilizing various embodiments of a Y-axis motion system ofthe present teachings. Additionally, for various embodiments of grippermotion control assembly 2650 of FIG. 6, a master-slave control systemcan be used for controlling the first voice coil assembly 2630A andsecond voice coil assembly 2630B of FIG. 6, so that if one voice coilresponds to correct a theta-Z (θ-Z) orientation, the other voice coil iscontrolled in an equal and offsetting fashion. Various embodiments ofgripper motion control assembly 2650 can maintain the orientation of asubstrate parallel to the Y-axis of travel to within +/−4300microradians. Accordingly, gripper motion control assembly 2650 ofY-axis motion system 2600 can maintain substrate orientation with a highdegree of precision parallel to the Y-axis direction of travel in ahorizontal plane determined, for example, by the fly height of asubstrate.

FIG. 8 is a top view of Y-axis motion system 2600, showing gripperassembly 2610, Y-axis carriage assembly top plate 2624, and grippermotion control assembly 2650, similar to FIG. 4A, which indicates theposition of cross-section views for FIG. 8 and FIG. 9.

FIG. 9 illustrates generally a cross section view through a voice coilassembly; specifically designated in FIG. 8, as a cross-section viewthrough voice coil assembly 2630B, though any description given hereinregarding the section view of FIG. 9 applies equally to voice coilassembly 2630A. Voice coil gripper frame mounting block 2648B isdepicted in FIG. 9 positioned between first air bearing 2641A and secondair bearing 2641B of voice coil assembly 2630B. Associated with each offirst air bearing 2641A and second air bearing 2641B is an air bearingspherical pivot; 2643A and 2643B, respectively. Air bearing sphericalpivot; 2643A associated with first air bearing 2641A and air bearingspherical pivot 2643B associated with first air bearing 2641B allow eachair bearing to float in theta-X (θ-X) and theta-Y (θ-Y), so that firstair bearing 2641A and second air bearing 2641B remain in a paralleldisposition with respect to mounting block 2648B. In addition to beingpositioned between first air bearing 2641A and second air bearing 2641B,voice coil gripper frame mounting block 2648B is also affixed to voicecoil holder 2647. Voice coil holder 2647 and voice coil magnet base arehoused inside voice coil housing second side 2633. Voice coil holder2647 is depicted in FIG. 9 as associated with coil magnet base 2649.During operation, the force of movement of voice coil magnet base 2649is translated to voice coil magnet holder 2647, which is translated tovoice coil gripper frame mounting block 2648B, and then to gripper frame2614 thereby. As previously discussed herein, various embodiments of agripper motion control assembly 2650 can use a master-slave control ofthe two voice coil assemblies, so that the two voice coils actsynchronously to maintain a gripper assembly orientation relative to thedirection of travel. Also depicted in FIG. 9 are vacuum manifold 2618 ofgripper assembly 2610, which is in flow communication with vacuum groove2617. As depicted in FIG. 9, the plurality of vacuum sockets depicted inFIG. 4B can be in flow communication with vacuum manifold 2618 viavacuum groove 2617.

FIG. 10 illustrates generally a cross section view through center pivotassembly 2660 as designated in FIG. 8. Pivot assembly 2660 can includeair bushing housing 2662, which can house first air bushing 2664A andsecond air busing 2664B. First air bushing 2664A and second air busing2664B can be configured around center shaft 2666; the use of two airbushings imparting a requisite system stiffness. First air bushing 2664Aand second air busing 2664B can be fabricated from a porous material,such as porous graphite, to ensure an even flow of a gas, such as aninert gas, can be evenly distributed around center shaft 2666. Centershaft 2666 can be held by upper clamp 2665 and lower clamp 2667, whichcan be secured to carriage assembly top plate 2624. Center pivot adaptorplate 2669 can be configured to affixed air bushing housing 2662 togripper frame 2614. In that regard, any theta-Z (θ-Z) rotation of airbushing assembly 2660 as a result of carriage assembly movement will betranslated to gripper assembly 2610 in response. Also depicted in FIG.10 are carriage assembly air bearing 2638D (see FIG. 4B) and carriageassembly air bearing 2638H (see FIG. 5B).

As previously discussed herein, maintaining a controlled environmentwithin the printing enclosure is paramount for various processes relatedto the manufacture of various OLED devices. According to variousembodiments of a gas enclosure system of the present teachings,environmental control of an interior volume defined by a gas enclosureassembly can include control of lighting, for example, by the number andplacement of lights of a specific wavelength, control of particulatematter using various embodiments of a particle control system, controlof reactive gas species using various embodiments of a gas purificationsystem, and temperature control of a gas enclosure assembly usingvarious embodiments of a thermal regulation system, as will be discussedin more detail subsequently herein. One aspect of thermal regulationrelates to minimizing heat loads within an enclosed printing system, forexample, as given by the design of the Y-axis motion system aspreviously described herein.

In addition to the Y-axis motion system, and with respect to theschematic shown in FIG. 11, minimizing the heat load can also includeminimizing the heat load of a motor used for controlling the movement ofthe Z-axis moving plate by utilizing a pneumatic counterbalance. In FIG.11, control loop 100 can be used to ensure that current driving Z-axismotor 2305 can be optimized during operation; particularly under load,as increasing the current to Z-axis motor 2305 will increase the motortemperature. One disadvantage of such motor heating can be the loss ofprinting accuracy due to thermal expansion of the of the motor and motorassembly. Additionally, as previously noted herein, control of heatdissipation is one aspect of environmental control of an enclosedprinting system. Accordingly, control loop 100 of FIG. 11 is shown toinclude pneumatic counterbalance system 2309, which can compensate forthe load on Z-axis motor 2305 by providing an automated counterbalancingforce against a load to minimize motor current, thereby minimizing motorheating.

In FIG. 11, Z_(cmd) input 105 is a commanded Z-axis position for aprinthead assembly, such as first printhead assembly 2501 and secondprinthead assembly 2502 of FIG. 1C. Referring to FIG. 1C, recalling,first printhead assembly 2501 and second printhead assembly 2502 can bemounted on first Z-axis moving plate 2310 and second Z-axis moving plate2312, respectively. First Z-axis moving plate 2310 and second Z-axismoving plate 2312, are mounted to first X-axis carriage assembly 2301and second X-axis carriage assembly 2302, respectively. In that regard,each printhead assembly can be positioned in an X,Z direction relativeto a substrate, such as substrate 2050 of FIG. 1C. During an exemplaryprocess step, for example, but not limited by, a printing process,Z_(cmd) input 105 can be received by motor controller C_(M) 110 and acurrent associated with the a commanded Z-axis position, i_(cmd) 115,can be sent to a motor drive D 120, so that Z-axis linear motor 2305 canmove a Z-axis moving plate, such as first Z-axis moving plate 2310 andsecond Z-axis moving plate 2312 of FIG. 1C. The exact position of aZ-axis moving plate in the Z-axis direction can be measured usingencoder 2303, which information regarding the exact Z-axis position canthen be fed back into motor controller C_(M) 110 until a commandedposition has been reached. Additionally, i_(cmd) 115, can be sent tolow-pass filter LP 130, which can act to filter current spikes, andadditionally to gate the controller response. Low-pass filter output 135can be sent to pneumatic controller C_(P) 140. Pneumatic controllerC_(P) 140 can then compute the counterbalance pressure PCB thatoptimizes i_(cmd) 115. During an exemplary process step, for example,but not limited by, the docking of a printhead assembly to a dockinggasket as previously discussed herein, there is a motor force, F_(M),required to counter a seal force, F_(S) as indicated in FIG. 11. Whilethe extra motor force enables a seal to be maintained, it requiresincreased motor current, which can result in increased heating of themotor.

As depicted in FIG. 11, to minimize the motor heating that would resultfrom increasing current in order to maintain motor force, F_(M) duringsealing of a printhead assembly against a docking gasket, pneumaticcounterbalance force, F_(CB), can be utilized. Vertical seal force F_(S)can be detected by continuously detecting current of motor 2305. Themagnitude and direction of seal force F_(S) can be reported to pneumaticcontroller C_(P) 140, which can calculate the required pneumaticcounterforce required, and can send commanded counterbalance pressurePCB 145 to pressure regulator R 150. Pressure regulator R 150 can thensupply the commanded pressure to pneumatic counterbalance system 2309 inorder to exert pneumatic counterforce F_(CB). According to the presentteachings, control loop 100 acts in a fashion so that sum of all forces;sealing force F_(S), intrinsic tool environment force F_(E), pneumaticcounterforce F_(CB), motor force F_(M), and gravitational force F_(G)acting on the Z-axis assembly, is zero.

FIG. 12A depicts printing system 2000, showing first X-axis carriageassembly 2301 and second X-axis carriage assembly 2302 without aprinthead assembly mounted thereupon. In FIG. 12B, a front view ofX-axis carriage assembly 2301 mounted to bridge 2130 is depicted inwhich pneumatic counterbalance system 2309 can include first pneumaticcylinder 2307A and second pneumatic cylinder 2307B. Though an example ofuse of control loop 100 was given for a process of docking a printheadassembly with a gasket, control loop 100 can be utilized for numerouspurposes. For example, during a printing operation, a pneumaticcounterbalance system, such as pneumatic counterbalance system 2309, canoperate in response to various embodiments of a pneumatic counterbalancecontrol loop to support a Z-axis moving plate and any associated load inorder to minimize the current to a motor 2305 of FIG. 11 duringprinting. Additionally, various embodiments of a pneumaticcounterbalance control loop, such as control loop 100 of FIG. 11, can beused for parameter monitoring of a printing system. For example, theglide of Z-axis moving plate may change over time, producing increasedfriction due to wear and aging. The increased load to a Z-axis movingplate motor as a result of increased friction can be offset usingvarious embodiments of a pneumatic counterbalance control loop andassociated systems. By way of another non-limiting example, changes inpressure monitored by pneumatic controller C_(P) can be monitored as aquality metric to initiate unscheduled maintenance on the Z-axis motionsystem before a failure is evident. It should be noted that while someexamples were given with respect to a specific carriage assembly,various embodiments of a pneumatic counterbalance control loop andassociated systems are generally applicable to any carriage assembly andany load of the present teachings.

As depicted in FIG. 13, gas enclosure 1000A can house printing system2000A. Gas enclosure system 500A having features as described forvarious embodiments of gas enclosure system 500 of FIG. 18, whileprinting system 2000A can have all the features described for printingsystem 2000 of FIG. 17. Printing system 2000A can have printing systembase 2100, which can be supported by at least two sets of isolators suchas isolator set 2110 that includes isolators 2110A and 2110B of FIG. 13.Y-axis motion system 2350 can be mounted on printing system base 2100.Substrate 2050 can be floatingly supported by substrate floatation table2200. Printing system base 2100 can support first riser 2120 and secondriser 2122, upon which bridge 2130 can be mounted. Printing systembridge 2130 can support first X-axis carriage assembly 2301, upon whichprinthead device assembly 2500 can be mounted, and second X-axiscarriage assembly 2302, upon which camera assembly 2550 can be mounted.Additionally, gas enclosure 1000A can have auxiliary panel assembly1330, which can enclose printhead management system 2701, as well as awaste containment system for the bulk ink delivery system. Auxiliarypanel assembly 1330 can be in flow communication with the remainingworking volume of gas enclosure 1000A through printhead assembly opening1342. Various embodiments of a bulk ink delivery system can be externalto gas enclosure 1000A and in flow communication with variousembodiments of a local ink delivery system, which can be proximal toprinthead device assembly 2500 on first X-axis carriage assembly 2301.

FIG. 14 is a schematic depiction of various embodiments of bulk inkdelivery system 3300, which can be in flow communication with local inkdelivery system 3500. Bulk ink delivery system (BIDS) 3300 can have bulkink supply system 3310, which can include first BIDS ink supply lineL_(B1) in flow communication with a first ink source, as well as asecond BIDS ink supply line L_(B2) in flow communication with a secondink source. First BIDS ink supply line L_(B1) and second BIDS ink supplyline L_(B2) can have first BIDS ink supply safety valve V_(B1) andsecond BIDS ink supply safety valve V_(B2), respectively. First BIDS inksupply safety valve V_(B1) and second BIDS ink supply safety valveV_(B2) can be used to isolate the first ink supply source and second inksupply source from lines upstream, for example, when the ink supplycontainers need to be changed or refilled. First BIDS ink supply valveV_(B3) is open when first ink supply container, Ink 1, is in use.Similarly, second BIDS ink supply valve V_(B4) is open when second inksupply container, Ink 2, is in use.

Though two ink supply sources are indicated in FIG. 14, a plurality ofink supply containers can be included in bulk ink supply system 3310,and can act as sequential supply sources of ink. For example, as shownin FIG. 14, when the level of ink in first ink supply container, Ink 1,is at the low level indicator, first BIDS ink supply safety valve V_(B1)can be closed and first BIDS ink supply valve V_(B3) can be closed, sothat first ink supply container, Ink 1, can be isolated and eitherrefilled or replaced. Following the isolation of Ink 1, second BIDS inksupply safety valve V_(B2) can be opened and second BIDS ink supplyvalve V_(B4) can be opened so that second ink supply container, Ink 2,can act as the source of ink supply for a gas enclosure system, such asgas enclosure system 500A of FIG. 13. First BIDS ink supply line L_(B1),and second BIDS ink supply line L_(B2) can be joined at a T-junctionusing two valves, as shown in FIG. 14, or a 3-way valve can be used.Either one of first BIDS ink supply line L_(B1), or second BIDS inksupply line can be in flow communication with third BIDS line L_(B3),depending on which ink supply source is in use. Third BIDS line L_(B3)can be in flow communication with first BIDS pump P_(B1), which can be apneumatic piston syringe or metering pump compatible with the chemistryof the ink used. During processes requiring ink flow from bulk inksupply system 3310, fifth BIDS valve V_(B5) is in an open position,allowing flow between third BIDS line L_(B3) and forth BIDS line L_(B4).Forth BIDS line L_(B4) passes through filter 3312 and is in flowcommunication with fifth BIDS line L_(B5), which is in flowcommunication with a degasser for removing dissolved gases in an inkfrom an bulk in supply source of bulk ink supply system 3310. Finally,after being degassed, ink can flow through sixth BIDS line L_(B6), whichis in flow communication with local ink delivery system 3500. Sixth BIDSline L_(B6) can be controlled at the outlet by a suckback valve locatedin local ink delivery system 3500, as shown in FIG. 14.

In addition to bulk ink supply system 3310, bulk ink delivery system3300 can have BIDS maintenance system 3330 that can include a solventline, seventh BIDS solvent line L_(B7), as well as an inert gas line,eighth BIDS gas line L_(B8), depicted in FIG. 14 as utilizing a nitrogensource. Seventh BIDS solvent line L_(B7), can have can be in flowcommunication with second BIDS pump P_(B2), which can be a pneumaticpiston syringe or metering pump compatible with the chemistry of thesolvent used. Seventh BIDS solvent line L_(B7) and eighth BIDS gas lineL_(B8) can have first BIDS maintenance system safety valve V_(B6) andsecond BIDS maintenance system safety valve V_(B7), respectively, whichare in a normally closed position during processing, but can beselectively opened during, for example, but not limited by, amaintenance procedure. For example, during a maintenance procedure, theBIDS valves associated with bulk ink supply system 3310, BIDS valvesV_(B1) through V_(B5), would remain in a closed position. If amaintenance procedure utilizing a solvent is implemented, then BIDSvalves V_(B6), V_(B8), and V_(B10) can be opened, so that solvent line,seventh BIDS solvent line L_(B7) can be in flow communication with sixthBIDS line L_(B6), which is in flow communication with local ink deliverysystem 3500, as previously described. Additionally, if during amaintenance procedure an inert gas is utilized, then BIDS valves V_(B7),V_(B9), and V_(B10) can be opened, so that inert gas line, eighth BIDSgas line L_(B8), can be in flow communication with sixth BIDS lineL_(B6), which is in flow communication with local ink delivery system3500, as previously described. It should be mentioned that, similarly tothat described for bulk ink supply system 3310, seventh BIDS solventline L_(B7), and eighth BIDS gas line L_(B8) can be joined at aT-junction using two valves, as shown in FIG. 14, to be in flowcommunication with ninth BIDS line L_(B9). Likewise, third BIDS lineL_(B3), and ninth BIDS line L_(B9) can be joined at a T-junction usingtwo valves, as shown in FIG. 14, to be in flow communication with forthBIDS line L_(B4). In either case, a 3-way valve can be used in anequivalent fashion to a T-junction using two valves.

As depicted in FIG. 14, local ink delivery system 3500 according tovarious systems and methods of the present teachings can include localink supply system 3600, printhead ink delivery system 3700 and local inkwaste assembly 3800. For various embodiments of the present teachings,local ink supply system 3600 can be in flow communication with bulk inkdelivery system 3300 via sixth BIDS line L_(B6), while local ink wasteassembly 3800 can be in flow communication with bulk ink delivery systemwaste assembly 3340 through tenth BIDS line L_(B10). Tenth BIDS lineL_(B10), can have third BIDS pump P_(B3), which can be a pneumaticpiston syringe or metering pump compatible with the chemistry of thewaste being removed from printhead ink delivery system 3700.

In FIG. 15, a schematic depiction of various embodiments of bulk inkdelivery system 3301 is shown. Bulk ink delivery system 3301 can be inflow communication with local ink delivery system 3501. For variousembodiments of bulk ink delivery system 3301, pump P_(B1) can be ametering pump that can effectively pump both liquid and gaseous fluids.In that regard, both bulk ink supply system 3311 and maintenance system3331 of bulk ink delivery system 3301 can utilize metering pump P_(B1)for flow control. As depicted in FIG. 15, metering pump P_(B1) providesa controllable manifold system that has three input lines, with thepotential for three output lines; of which two are indicated in FIG. 15,all of which are controlled using metering pump valves as indicated. Thenumber of controllable input and output lines can vary, according tovarious embodiments of metering pumps. Various embodiments of meteringpumps utilized in embodiments of bulk ink delivery systems of thepresent teachings can have attributes that can include, for example, butnot limited by, capable of controlling both liquid and gaseous fluids,corrosion resistant polymeric surfaces in contact with fluid flow toprevent corrosion and contamination, zero dead volume connectionspreventing cross-contamination, minimum hold-up volume for fast primingusing a minimum volume of various inks, and valves with suckbackcapability. Accordingly, various embodiments of bulk ink delivery system3301 can utilize fewer valves and pumps than various embodiments of bulkink delivery system 3300 of FIG. 14.

Bulk ink delivery system (BIDS) 3301 of FIG. 15 can have bulk ink supplysystem 3311 that can have first BIDS ink supply line L_(B1) in flowcommunication with a first ink source, and second BIDS ink supply lineL_(B2) in flow communication with a second ink source. First BIDS inksupply line L_(B1) and second BIDS ink supply line L_(B2) can controlledby first BIDS valve V_(B1) and second BIDS valve V_(B2), respectively,which can part of the assembly of multi-port metering pump P_(B1), asindicated in FIG. 15. In addition to providing flow control for bulk inksupply system 3311, given the capability that metering pump P_(B1) hasfor controllably handling a variety of different fluids with minimumhold-up volume, metering pump P_(B1) can also be used for controllablyhandling maintenance system 3331. For example, in FIG. 15, third BIDSsolvent supply line L_(B3) can be in flow communication with a solventsource and forth BIDS gas supply line L_(B4) can be in flowcommunication with an inert gas source, for example, a nitrogen sourceas indicated in FIG. 15. Third BIDS solvent supply line L_(B3) and forthBIDS gas supply line L_(B4) can be controlled by third BIDS solventsupply valve V_(B3) and forth BIDS gas supply valve V_(B4),respectively. As depicted in FIG. 15, third BIDS solvent supply lineL_(B3) and forth BIDS gas supply line L_(B4) can be in flowcommunication with fifth BIDS line L_(B5), which can be controlled byfifth BIDS maintenance system supply valve V_(B5). Fifth BIDSmaintenance system supply valve V_(B5) can part of the assembly ofmulti-port metering pump P_(B1), as indicated in FIG. 15. Third BIDSsolvent supply line L_(B3), and forth BIDS gas supply line L_(B4) can bejoined at a T-junction using two valves, as shown in FIG. 15, or a 3-wayvalve can be used. Third BIDS solvent supply valve V_(B3) and forth BIDSinert gas supply valve V_(B4) are in a normally closed position duringprocessing, but can be selectively opened during a maintenanceprocedure, as will be discussed in more detail subsequently, herein.

Initially for various embodiments of systems and methods of FIG. 15, forexample, before a printing procedure has begun, priming of ink linethrough the manifold system of metering pump P_(B1) can be done. Forexample, once an ink supply is available from first ink supply containerInk 1, first BIDS ink supply line L_(B1) can be primed with ink from Ink1 by opening first BIDS ink supply valve V_(B1) and BIDS waste linevalve V_(BW), while all other valves remain closed. With the valvestates so positioned, priming of first BIDS ink supply line L_(B1) canbe done, in which there is flow communication between first BIDS inksupply line L_(B1) and bulk ink delivery system waste assembly 3341through BIDS waste line L_(BW). After priming, during, for example, theinitiation of a printing process, first BIDS ink supply valve V_(B1) andsixth BIDS valve V_(B6) of metering pump P_(B1) can be open, while allother valves are closed. With the valve states so positioned, first inksupply container, Ink 1, is in flow communication with bulk ink deliverysystem 3301, which is in flow communication with local ink deliverysystem 3501. Second BIDS line L_(B2) can be primed with ink from Ink 2in a similar fashion as given in the example for priming first BIDS inksupply line L_(B1).

Though two ink supply sources are indicated in FIG. 15, a plurality ofink supply containers can be included in bulk ink supply system 3311,and can act as sequential supply sources of ink. For example, as shownin FIG. 15, when the level of ink in first ink supply container, Ink 1,is at the low level indicator, first BIDS ink supply valve V_(B1) ofmetering pump P_(B1) can be closed, so that first ink supply container,Ink 1, can be isolated and either refilled or replaced. Following theisolation of Ink 1, second BIDS ink supply valve V_(B2) of metering pumpP_(B1) can be opened, so that second ink supply container, Ink 2, canact as the source of ink supply for a gas enclosure system, such as gasenclosure system 500A of FIG. 13. Either one of first BIDS line inksupply L_(B1) or second BIDS ink supply line L_(B2) can be in flowcommunication with sixth BIDS line L_(B6), depending on which ink supplysource is in use. During processes requiring ink flow from bulk inksupply system 3311, first BIDS ink supply valve V_(B1) and sixth BIDSvalve V_(B6) of metering pump P_(B1) can be open, while all other valvesare closed, allowing flow between first BIDS ink supply line L_(B1) andsixth BIDS line L_(B6). Sixth BIDS line L_(B6) passes through filter3312 and is in flow communication with seventh BIDS line L_(B7), whichis in flow communication with a degasser for removing, for example, butnot limited by, dissolved gases in an ink from an bulk in supply sourceof bulk ink supply system 3311. Finally, after being degassed, ink canflow through eighth BIDS line L_(B8), which is in flow communicationwith local ink delivery system 3501. Unlike sixth BIDS line L_(B6) ofbulk ink supply system 3310 of FIG. 14, eighth BIDS line L_(B8) does notrequire a suckback valve located in local ink delivery system 3500, asshown in FIG. 14, when a metering pump, such as metering pump P_(B1) ofFIG. 15, can provide such control.

As previously discussed herein, in addition to bulk ink supply system3311, bulk ink delivery system 3301 of FIG. 15 can have BIDS maintenancesystem 3331. BIDS maintenance system 3331 can include third BIDS solventsupply line L_(B3) and forth BIDS gas supply line L_(B4), which can becontrolled by third BIDS solvent supply valve V_(B3) and forth BIDSinert gas supply valve V_(B4), respectively. As depicted in FIG. 15,third BIDS solvent supply line L_(B3) and forth BIDS gas supply lineL_(B4) can be in flow communication with fifth BIDS line L_(B5). FifthBIDS line L_(B5) can be controlled by fifth BIDS maintenance systemsupply valve V_(B5) of metering pump P_(B1). Additionally, for bulk inkdelivery system 3301 of FIG. 15, BIDS waste line L_(BW) can be in flowcommunication with bulk ink delivery system waste assembly 3341. BIDSwaste line L_(BW) can be controlled by BIDS waste line valve V_(BW) ofmetering pump P_(B1). Third BIDS solvent supply valve V_(B3), forth BIDSgas supply valve V_(B4), fifth BIDS maintenance system supply valveV_(B5), and BIDS waste line valve V_(BW) are in a normally closedposition during processing, but can be selectively opened during amaintenance procedure.

For example, during a maintenance procedure, the BIDS valves of meteringpump P_(B1) associated with bulk ink supply system 3311, BIDS valvesV_(B1), V_(B2), and V_(B6), would remain in a closed position. If amaintenance procedure utilizing a solvent purge is implemented, thenBIDS valves V_(B3), V_(B5), and V_(BW) can be opened, so that solventpriming can be done through fifth BIDS line L_(B5), which can be in flowcommunication bulk ink delivery system waste assembly 3341. Afterpriming, during a maintenance procedure utilizing solvent cleaning of,for example, lines within local ink delivery system 3501, then BIDSwaste line valve V_(BW) can be closed, and BIDS valves V_(B3), V_(B5),and V_(B6) can be opened, so that solvent can flow through fifth BIDSline L_(B5), which can be in flow communication with sixth BIDS lineL_(B6). Sixth BIDS line L_(B6) is in flow communication with local inkdelivery system 3500, as previously described, providing solvent flowthroughout local ink delivery system 3501, and eventually to bulk inkdelivery system waste assembly 3341 through ninth BIDS line L_(B9).Additionally, if a maintenance procedure utilizing an inert gas isimplemented, then BIDS valves V_(B4), V_(B5), and V_(B6) can be opened,so that inert gas can flow through fifth BIDS line L_(B5), which can bein flow communication with sixth BIDS line L_(B6). Sixth BIDS lineL_(B6) is in flow communication with local ink delivery system 3500, aspreviously described.

As depicted in FIG. 15, local ink delivery system 3501 according tovarious systems and methods of the present teachings can include localink supply system 3601, printhead ink delivery system 3701 and local inkwaste assembly 3801. For various embodiments of the present teachings,local ink supply system 3601 can be in flow communication with bulk inkdelivery system 3301 via eighth BIDS line L_(B8), while local ink wasteassembly 3801 can be in flow communication with bulk ink delivery systemwaste assembly 3341 through ninth BIDS line L_(B9). Ninth BIDS lineL_(B9) can have second BIDS pump P_(B2), which can be a pneumatic pistonsyringe or metering pump compatible with the chemistry of the wastebeing removed from printhead ink delivery system 3701.

FIG. 16 depicts a schematic section view of gas enclosure system 500A,that can include gas enclosure 1000A with local ink delivery system3500. As previously described herein, local ink delivery system 3500according to various embodiments of the present teachings can includelocal ink supply system 3600, printhead ink delivery system 3700 andlocal ink waste assembly 3800. As depicted in FIG. 16, sixth BIDS lineL_(E6) can be controlled by suckback valve V_(P1) located in local inkdelivery system 3500, so that ink can be delivered directly to a bulkink supply reservoir, which is part of local ink supply system 3600. Inthat regard, various embodiments of a bulk ink delivery system of thepresent teachings can bring an ink supply directly to a bulk supplyreservoir of ink reservoir local ink supply system 3600, which can be inflow communication with a bulk ink reservoir that is in flowcommunication with a dispensing reservoir in flow communication with,for example, a plurality of printhead devices, such as printhead devices2505 of FIG. 1C. As will be discussed in more detail herein, variousembodiments of printhead ink delivery system 3700 can utilize atwo-stage ink delivery assembly. Moreover, a local ink waste assemblyinternal a gas enclosure can be in flow communication with a bulk inkdelivery system waste assembly that is part of a bulk ink deliverysystem. Accordingly, various embodiments of a bulk ink delivery system,which can be substantially external to a gas enclosure system, can be inflow communication with a local ink delivery system internal a gasenclosure system in a fashion that avoids running ink lines to aprinthead assembly, such as printhead device assembly 2500 on firstX-axis carriage assembly 2301 of FIG. 1C, through a cable carrier. Assuch, a bulk replenishment system that is substantially external to agas enclosure is more readily accessible for service, such asreplenishing ink and solvent supplies, as well as changing linescarrying various inks and solvents.

FIG. 17 is a schematic view of a local ink delivery system including aprinthead ink delivery system according to the present teachings. Forvarious embodiments a local ink delivery system of the presentteachings, pneumatic control assembly IA can provide control betweenprimary dispensing reservoir IC and various pneumatic control sources,such as gas and vacuum sources. According to various embodiments of alocal ink delivery system of the present teachings, local ink deliveryline IB can be capable of proving fluidic distribution and controlbetween primary dispensing reservoir IC and local bulk ink reservoir ID.Primary dispensing reservoir IC can be in flow communication with aplurality of printheads IE through input manifold line IF. In theschematic representation of FIG. 17, three printheads are indicated foreach of 3 printhead device assemblies. Printhead assembly input manifoldline IF can be in flow communication with printhead assembly inputmanifold IG. Printhead assembly input manifold IG can be in flowcommunication with each of a plurality of printhead devices, where eachprinthead device can have at least three printheads, number sequentiallyas printhead 1 through printhead 9 in FIG. 17. The flow communicationbetween printhead assembly input manifold IG and each printhead devicecan be controlled by using printhead assembly manifold valves IG_(V1),IG_(V2) and IG_(V3). Finally, the plurality of printhead assemblies canbe in flow communication with a printhead assembly output waste line,which is a part of printhead output manifold IH. Printhead assemblyoutput waste line can be in flow communication with a local ink wasteassembly, which in turn is in flow communication with a bulk inkdelivery system waste assembly (see, for example, FIG. 14 and FIG. 15).The flow communication between printhead assembly output manifold IH andeach printhead device can be controlled by using printhead assemblymanifold line valves IH_(V1), IH_(V2) and IH_(V3).

FIG. 18A is a bottom expanded perspective view of printhead deviceassembly 2500, mounted on a printhead assembly positioning system, suchas first X-axis carriage assembly 2301 (see also FIG. 1C). First X-axiscarriage assembly 2301 can be positioned in an X-axis direction onprinting system bridge 2130 relative to a substrate, such as substrate2050 of FIG. 1C. As shown in FIG. 18A, service bundle housing 2410 ismounted to printing system bridge 2130. Service bundle housing 2410 cancontain various service bundles operatively connected from variousapparatuses and system to a gas enclosure system including a printingsystem. Various embodiments of a service bundle can include bundledoptical cables, electrical cables, wires and tubing, and the like, forproviding optical, electrical, mechanical, and fluidic functions forvarious assemblies and systems disposed within the interior of the gasenclosure system. During various process steps, such as printing andmaintenance steps, as X-axis carriage assembly 2301 moves printheaddevice assembly 2500 across printing system bridge 2130, various servicebundles move accordingly. Therefore, liquid ink lines in such servicebundles are subject to continuous flexure and wear. According to systemsand methods of the present teachings, a bulk ink delivery systemexternal a gas enclosure system can be in fluid communication with alocal ink delivery supply system internal to a gas enclosure system thatobviates the need to run ink lines through a service bundle located inservice bundle housing 2410. As such, a bulk replenishment system thatis substantially external to a gas enclosure is more readily accessiblefor service, such as replenishing ink and solvent supplies, as well asservicing or replacing various lines and valves.

As depicted in FIG. 18A printhead device assembly 2500 can haveprinthead assembly enclosure 2503, which can enclose a plurality ofprinthead devices 2505A, 2505B, and 2505C, mounted therein. For variousembodiments of printing system 2000 of FIG. 1C or printing system 2000Aof FIG. 13 and FIG. 16, a printhead device assembly can include betweenabout 1 to about 60 printhead devices, where each printhead device canhave between about 1 to about 30 printheads in each printhead device. Asdepicted in FIG. 18A, according to systems and methods of the presentteachings, printhead device assembly 2500 can have three printheaddevices, where each printhead device can have three printheads (see alsoFIG. 17). As will be discussed in more detail herein, given the numberof printhead devices and printheads requiring continual maintenance,printhead device assembly 2500 can be positioned over a maintenancesystem for ready placement or replacement of a printhead device or aprinthead.

As shown in the bottom perspective view of FIG. 18B, printhead deviceassembly 2500 can have printhead devices 2505A, 2505B, and 2505C mountedusing a kinematic mount, similar to what was described for the kinematicmounting of printhead unit 1000 of, for example, FIG. 13A. In thatregard, as will be discussed in more detail subsequently herein, variousembodiments of a kinematic mounting assembly for the vertical mountingof embodiments of a printhead device, such as printhead devices 2505A,2505B, and 2505C of FIG. 18B into a printhead device assembly, such asprinthead device assembly 2500 of FIG. 18B can utilize, for example, acanoe sphere and V-block assembly. In FIG. 18B, canoe sphere 1118A isdepicted for each printhead device 2505A, 2505B, and 2505C of FIG. 18B.

Additionally, camera assembly 2551 is shown mounted in printheadassembly enclosure 2503. For various embodiments of systems and methodsof the present teachings, a plurality of cameras can be mounted onvarious devices, apparatuses and assemblies to provide real-timevisualization of operations within a gas enclosure system, such as gasenclosure system 500A of FIG. 13. For example, camera assembly 2550 ofFIG. 13, and camera assembly 2551 of FIG. 18B can be utilized, forexample, but not limited by, navigation, as well as inspection. Variousembodiments of a printing system camera assembly can have differentspecifications regarding field of view and resolution. For example, onecamera can be a line scan camera for in situ particle inspection, whilea second camera can be used for the regular navigation of a substrate ina gas enclosure system, or for the location of a printhead deviceassembly relative to a substrate. Such a camera useful for regularnavigation can be an area scan camera having a field of view in therange of about 5.4 mm×4 mm with a magnification of about 0.9× to about10.6 mm×8 mm with a magnification of about 0.45×. In still otherembodiments, one camera can be a line scan camera for in situ particleinspection, while a second camera can be used for the precise navigationof a substrate in a gas enclosure system, for example, for substratealignment, or for the precise location of a printhead device assemblyrelative to a substrate. Such a camera can be useful for precisenavigation can be an area scan camera having a field of view of about0.7 mm×0.5 mm with a magnification of about 7.2×.

FIG. 19A and FIG. 19B depict various perspective views of printheaddevice 2505 according to various embodiments of a printhead device ofthe present teachings. As previously described herein, kinematicmounting of a printhead unit to a printing system can provide for arepeatable, strain-free positioning of various embodiments of aprinthead unit or a printhead device of the present teachings. Forexample, kinematic mounting assemblies described for the kinematicmounting of printhead unit 1000 can utilize a point contact kinematicassembly, such as a ball and V-block kinematic mounting assembly.Various embodiments of a kinematic mounting assembly for the verticalmounting of a plurality of printhead devices into a printhead deviceassembly can utilize a line contact kinematic assembly, for example, butnot limited by, a canoe sphere and V-block kinematic mounting assembly.Various embodiments of a line contact kinematic mounting assembly cancarry substantially more load, for example, at least about 100 timesmore load, than an equivalent kinematic mounting assembly providingpoint contact. Various embodiments of a kinematic mounting assemblyprovide significant stability for the repeatable, strain-freepositioning of the vertical mounting a printhead device into a printheaddevice assembly, as well as providing stability during the X-axismovement of a printhead device assembly by naturally resisting themovement in the X-axis direction.

In the top perspective view of FIG. 19A and bottom perspective view ofFIG. 19B, first canoe sphere mounting fixture 1116A for first canoesphere 1118A can be seen, as well as second canoe sphere mountingfixture 1116B for second canoe sphere 1118B. Third canoe sphere mountingfixture 1116C is apparent in FIG. 19A and FIG. 19B, for which a thirdcanoe sphere can be mounted on back of printhead device 2505. Thepositions of a set of canoe spheres 1118A, 1118B, and 1118C, once eachis engaged in a mating surface of a V-block mount, can be used for therepeatable and strain-free vertical bottom insertion of printhead device2505 into a printhead device assembly, such as printhead device assembly2500 of FIG. 18A and FIG. 18B. As shown in FIG. 19B, each printheaddevice can have 3 end-user selected printhead assemblies, 200A, 200B,and 200C. Printhead device 2505 can have first quick-coupling connector1110A, providing ease of connecting fluidic lines coming into printheaddevice 2505, as well as second quick-coupling connector 1110B, providingease of connecting fluidic lines going from printhead device 2505. Asshown in the schematic depiction of the fluidic system in FIG. 17 forvarious embodiments of a local ink delivery system, the flowcommunication from the local ink delivery system for each printheaddevice in a printhead device assembly can be controlled by usingprinthead assembly manifold valves IG_(V1), IG_(V2) and IG_(V3). Also asshown in FIG. 17, the flow communication from each printhead device in aprinthead device assembly to a printhead output manifold can becontrolled by using printhead assembly manifold valves IH_(V1), IH_(V2)and IH_(V3), which are part of printhead output manifold IH of FIG. 17.Various embodiments of a printhead output manifold can be in flowcommunication with a local ink waste assembly, such as local ink wasteassembly 3800, for example, of FIG. 16. In FIG. 19A and FIG. 19B, inputprinthead assembly manifold valve IG_(V) and output printhead assemblymanifold valve IH_(V) are shown for printhead device 2505.

FIG. 19C depicts printhead device kinematic mounting plate 1340 withfirst V-block 1348A, second V-block 1348B, and third V-block 1348C,which are mating surfaces for first canoe sphere 1118A, second canoesphere 1118B, and third canoe sphere 1118C, respectively of FIG. 19A andFIG. 19B. First V-block 1348A, second V-block 1348B, and third V-block1348C can be affixed to printhead device kinematic mounting plate 1340using first V-block mounting fixture 1342A, second V-block mountingfixture 1342B, and third V-block mounting fixture 1342C, respectively.As depicted in FIG. 19A through FIG. 19C, first V-block 1348A is amating surface for first canoe sphere 1118A, second V-block 1348B is amating surface for second canoe sphere 1118B, and third V-block 1348C isa mating surface for third canoe sphere 1118C. FIG. 19D depictsprinthead device unit 1300, with printhead device 2505 mounted onprinthead device kinematic mounting plate 1340, using canoe sphere andV-block kinematic mounts. For example, in FIG. 19D, first canoe sphere1118A as shown in FIG. 19B is mounted to first canoe sphere mountingfixture 1116A, and is engaged in first V-block 1348A, which is mountedon first V-block mounting fixture 1342A. First V-block mounting fixture1342A is one of three V-block mounting fixtures mounted to printheaddevice kinematic mounting plate 1340, as previously described herein. Inthat regard, the coupling of first canoe sphere 1118A to first V-block1348A for printhead device unit 1300 of FIG. 19D is exemplary of thecoupling of second canoe sphere 1118B and third canoe sphere 1118C withsecond V-block 1348B and third V-block 1348C, respectively. In additionto printhead device kinematic mounting plate 1340, various embodimentsof a mounting assembly for a printhead device unit, such as printheaddevice unit 1300 of FIG. 19D, can include printhead device frontmounting plate 1341 as well as first printhead device side mountingplate 1343A and second printhead device side mounting plate 1343B. Eachquick-coupling connector as shown in FIG. 19A and FIG. 19B can bemounted to a printhead device side mounting plate, as depicted in FIG.19D for first quick-coupling connector 1110A mounted to first printheaddevice side mounting plate 1343A.

According to various systems and methods of the present teaching aprinthead device, such as printhead devices 2505A, 2505B, and 2505C ofFIG. 18A and FIG. 18B can be manually or automatically inserted from thebottom of printhead device assembly 2500. For example, as depicted inFIG. 1D printhead installation or replacement can be done robotically.As previously discussed herein in reference to FIG. 13, a gas enclosure,such as gas enclosure 1000A, can have auxiliary panel assembly 1330,which can enclose printhead management system 2701. In FIG. 1D, theinstallation or replacement of a printhead device or printhead, can bedone in auxiliary panel assembly 1330 using robot 2530. Printheadreplacement module 2713 of printhead management system 2701 FIG. 1D caninclude a docking station for a printhead device having at least oneprinthead, as well as a storage receptacle for a plurality of printheaddevices, as well as a plurality of printheads. Each printhead assemblyof the present teachings can include between about 1 to about 60printhead devices, and as each printhead device can have between about 1to about 30 printheads (for example, but not limited by, see printheaddevice assembly 2500 of FIG. 1C and FIG. 18A). Accordingly, in additionto having between 1 to about 60 printhead devices, various embodimentsof a printing system of the present teachings can have between about 1to about 1800 printheads. As previously discussed herein, a printheaddevice, such as printhead device 2505 of FIG. 19A and FIG. 19B can beinstalled or replaced through the strain-free bottom insertion of aprinthead device in a printhead assembly, such as printhead deviceassembly 2500 of FIG. 23A and FIG. 18B, of which a bottom view isindicated in FIG. 1D.

FIG. 20 is a schematic diagram showing a gas enclosure system 500B.Various embodiments of a gas enclosure system 500B according to thepresent teachings can comprise gas enclosure assembly 1000B for housinga printing system, gas purification loop 3130 in fluid communication gasenclosure assembly 1000B, and at least one thermal regulation system3140. Additionally, various embodiments of gas enclosure system 500B canhave pressurized inert gas recirculation system 3000, which can supplyinert gas for operating various devices, such as a substrate floatationtable for an OLED printing system. Various embodiments of a pressurizedinert gas recirculation system 3000 can utilize a compressor, a blowerand combinations of the two as sources for various embodiments ofpressurized inert gas recirculation system 3000, as will be discussed inmore detail subsequently herein. Additionally, gas enclosure system 500Bcan have a circulation and filtration system internal to gas enclosuresystem 500B (not shown).

As depicted in FIG. 20, for various embodiments of a gas enclosureassembly according to the present teachings, the design of a filtrationsystem can separate the inert gas circulated through gas purificationloop 3130 from the inert gas that is continuously filtered andcirculated internally for various embodiments of a gas enclosureassembly. Gas purification loop 3130 includes outlet line 3131 from gasenclosure assembly 1000B, to a solvent removal component 3132 and thento gas purification system 3134. Inert gas purified of solvent and otherreactive gas species, such as oxygen and water vapor, are then returnedto gas enclosure assembly 1000B through inlet line 3133. Gaspurification loop 3130 may also include appropriate conduits andconnections, and sensors, for example, oxygen, water vapor and solventvapor sensors. A gas circulating unit, such as a fan, blower or motorand the like, can be separately provided or integrated, for example, ingas purification system 3134, to circulate gas through gas purificationloop 3130. According to various embodiments of a gas enclosure assembly,though solvent removal system 3132 and gas purification system 3134 areshown as separate units in the schematic shown in FIG. 20, solventremoval system 3132 and gas purification system 3134 can be housedtogether as a single purification unit.

Gas purification loop 3130 of FIG. 20 can have solvent removal system3132 placed upstream of gas purification system 3134, so that inert gascirculated from gas enclosure assembly 1000B passes through solventremoval system 3132 via outlet line 3131. According to variousembodiments, solvent removal system 3132 may be a solvent trappingsystem based on adsorbing solvent vapor from an inert gas passingthrough solvent removal system 3132 of FIG. 20. A bed or beds of asorbent, for example, but not limited by, such as activated charcoal,molecular sieves, and the like, may effectively remove a wide variety oforganic solvent vapors. For various embodiments of a gas enclosuresystem cold trap technology may be employed to remove solvent vapors insolvent removal system 3132. As previously discussed herein, for variousembodiments of a gas enclosure system according to the presentteachings, sensors, such as oxygen, water vapor and solvent vaporsensors, may be used to monitor the effective removal of such speciesfrom inert gas continuously circulating through a gas enclosure system,such as gas enclosure system 500B of FIG. 20. Various embodiments of asolvent removal system can indicate when sorbent, such as activatedcarbon, molecular sieves, and the like, has reached capacity, so thatthe bed or beds of sorbent can be regenerated or replaced. Regenerationof a molecular sieve can involve heating the molecular sieve, contactingthe molecular sieve with a forming gas, a combination thereof, and thelike. Molecular sieves configured to trap various species, includingoxygen, water vapor, and solvents, can be regenerated by heating andexposure to a forming gas that comprises hydrogen, for example, aforming gas comprising about 96% nitrogen and 4% hydrogen, with saidpercentages being by volume or by weight. Physical regeneration ofactivated charcoal can be done using a similar procedure of heatingunder an inert environment.

Any suitable gas purification system can be used for gas purificationsystem 3134 of gas purification loop 3130 of FIG. 20. Gas purificationsystems available, for example, from MBRAUN Inc., of Statham, N.H., orInnovative Technology of Amesbury, Mass., may be useful for integrationinto various embodiments of a gas enclosure assembly according to thepresent teachings. Gas purification system 3134 can be used to purifyone or more inert gases in gas enclosure system 500B, for example, topurify the entire gas atmosphere within a gas enclosure assembly. Aspreviously discussed herein, in order to circulate gas through gaspurification loop 3130, gas purification system 3134 can have a gascirculating unit, such as a fan, blower or motor, and the like. In thatregard, a gas purification system can be selected depending on thevolume of the enclosure, which can define a volumetric flow rate formoving an inert gas through a gas purification system. For variousembodiments of gas enclosure system having a gas enclosure assembly witha volume of up to about 4 m³; a gas purification system that can moveabout 84 m³/h can be used. For various embodiments of gas enclosuresystem having a gas enclosure assembly with a volume of up to about 10m³; a gas purification system that can move about 155 m³/h can be used.For various embodiments of a gas enclosure assembly having a volume ofbetween about 52-114 m³, more than one gas purification system may beused.

Any suitable gas filters or purifying devices can be included in the gaspurification system 3134 of the present teachings. In some embodiments,a gas purification system can comprise two parallel purifying devices,such that one of the devices can be taken off line for maintenance andthe other device can be used to continue system operation withoutinterruption. In some embodiments, for example, the gas purificationsystem can comprise one or more molecular sieves. In some embodiments,the gas purification system can comprise at least a first molecularsieve, and a second molecular sieve, such that, when one of themolecular sieves becomes saturated with impurities, or otherwise isdeemed not to be operating efficiently enough, the system can switch tothe other molecular sieve while regenerating the saturated ornon-efficient molecular sieve. A control unit can be provided fordetermining the operational efficiency of each molecular sieve, forswitching between operation of different molecular sieves, forregenerating one or more molecular sieves, or for a combination thereof.As previously discussed herein, molecular sieves may be regenerated andreused.

Thermal regulation system 3140 of FIG. 20 can include at least onechiller 3142, which can have fluid outlet line 3141 for circulating acoolant into a gas enclosure assembly, and fluid inlet line 3143 forreturning the coolant to the chiller. An at least one fluid chiller 3142can be provided for cooling the gas atmosphere within gas enclosuresystem 500B. For various embodiments of a gas enclosure system of thepresent teachings, fluid chiller 3142 delivers cooled fluid to heatexchangers within the enclosure, where inert gas is passed over afiltration system internal the enclosure. At least one fluid chiller canalso be provided with gas enclosure system 500B to cool heat evolvingfrom an apparatus enclosed within gas enclosure system 500B. Forexample, but not limited by, at least one fluid chiller can also beprovided for gas enclosure system 500B to cool heat evolving from anOLED printing system. Thermal regulation system 3140 can compriseheat-exchange or Peltier devices and can have various coolingcapacities. For example, for various embodiments of a gas enclosuresystem, a chiller can provide a cooling capacity of from between about 2kW to about 20 kW. Various embodiments of a gas enclosure system canhave a plurality of fluid chillers that can chill one or more fluids. Insome embodiments, the fluid chillers can utilize a number of fluids ascoolant, for example, but not limited by, water, anti-freeze, arefrigerant, and a combination thereof as a heat exchange fluid.Appropriate leak-free, locking connections can be used in connecting theassociated conduits and system components.

As previously discussed herein, the present teachings disclose variousembodiments of a gas enclosure system that can include a printing systemenclosure defining a first volume and an auxiliary enclosure defining asecond volume. Various embodiments of a gas enclosure system can have anauxiliary enclosure that can be sealably constructed as a section of gasenclosure assembly. According to systems and methods of the presentteachings, an auxiliary enclosure can be sealable isolated from aprinting system enclosure, and can be opened to an environment externala gas enclosure assembly without exposing a printing system enclosure tothe external environment. Such physical isolation of an auxiliaryenclosure to perform, for example, but not limited by, various printheadmanagement procedures, can be done to eliminate or minimize the exposureof a printing system enclosure to contamination, such as air and watervapor and various organic vapors, as well as particulate contamination.Various printhead management procedures that can include measurement andmaintenance procedures on a printhead assembly can be done with littleor no interruption of a printing process, thereby minimizing oreliminating gas enclosure system downtime.

For a gas enclosure system having a printing system enclosure defining afirst volume and an auxiliary enclosure defining a second volume, bothvolumes can be readily integrated with gas circulation, filtration andpurification components to form a gas enclosure system that can sustainan inert, substantially low-particle environment for processes requiringsuch an environment with little or no interruption of a printingprocess. According to various systems and methods of the presentteachings, a printing system enclosure may be introduced to a level ofcontamination that is sufficiently low that a purification system canremove the contamination before it can affect a printing process.Various embodiments of an auxiliary enclosure can be a substantiallysmaller volume of the total volume of a gas enclosure assembly and canbe readily integrated with gas circulation, filtration and purificationcomponents to form an auxiliary enclosure system that can rapidlyrecover an inert, of a low-particle environment after exposure to anexternal environment, thereby providing little or no interruption of aprinting process.

Additionally, various embodiments of an auxiliary enclosure can bereadily integrated with a dedicated set of environmental regulationsystem components, such as lighting, gas circulation and filtration, gaspurification, and thermostating components. In that regard, variousembodiments of a gas enclosure system that include an auxiliaryenclosure that can be sealably isolated as a section of gas enclosureassembly can have a controlled environment that is set to be uniformwith a first volume defined by a gas enclosure assembly housing aprinting system. Further, various embodiments of a gas enclosure systemincluding an auxiliary enclosure that can be sealably isolated as asection of gas enclosure assembly can have a controlled environment thatis set to be different than the controlled environment of a first volumedefined by a gas enclosure assembly housing a printing system.

While the examples above mentioning cooling capacities and chillingapplications, the examples above can also be applied to applicationswhere including buffering of substrates in a controlled environment, orfor applications where circulating gas can be maintained at atemperature similar to other portions of the system, such as to avoidunwanted heat transfer from substrates being fabricated or to avoiddisruption of temperature uniformity across a substrate or betweensubstrates.

FIGS. 21A and 21B illustrate generally examples of a gas enclosuresystem for integrating and controlling non-reactive gas and clean dryair (CDA) sources such as can be used to establish the controlledenvironment referred to in other examples described elsewhere herein,and such as can include a supply of pressurized gas for use with afloatation table. FIGS. 22A and 22B illustrate generally examples of agas enclosure system for integrating and controlling non-reactive gasand clean dry air (CDA) sources such as can be used to establish thecontrolled environment referred to in other examples described elsewhereherein, and such as can include a blower loop to provide, for example,pressurized gas and at least partial vacuum for use with a floatationtable. FIG. 22C illustrates generally a further example of a system forintegrating and controlling one or more gas or air sources, such as toestablish floatation control zones included as a portion of a floatationconveyance system.

Various examples described herein include enclosed modules that can beenvironmentally-controlled. Enclosure assemblies and correspondingsupport equipment can be referred to as a “gas enclosure system” andsuch enclosure assemblies can be constructed in a contoured fashion thatreduces or minimizes an internal volume of a gas enclosure assembly, andat the same time provides a working volume for accommodating variousfootprints of printing system components, such as the deposition (e.g.,printing), holding, loading, or treatment modules described herein. Forexample, a contoured gas enclosure assembly according to the presentteachings can have a gas enclosure volume of between about 6 m³ to about95 m³ for various examples of a gas enclosure assembly of the presentteachings covering, for example, substrate sizes from Gen 3.5 to Gen 10.Various examples of a contoured gas enclosure assembly according to thepresent teachings can have a gas enclosure volume of, for example, butnot limited by, of between about 15 m³ to about 30 m³, which might beuseful for printing of, for example, but not limited by, Gen 5.5 to Gen8.5 substrate sizes or other substrate sizes. Various examples of anauxiliary enclosure can be constructed as a section of gas enclosureassembly and readily integrated with gas circulation and filtration, aswell as purification components to form a gas enclosure system that cansustain a controlled, substantially low-particle environment forprocesses requiring such an environment.

As shown in FIG. 21A and FIG. 22A, various examples of a gas enclosuresystem can include a pressurized non-reactive gas recirculation system.Various examples of a pressurized gas recirculation loop can utilize acompressor, a blower and combinations thereof. According to the presentteachings, several engineering challenges were addressed in order toprovide for various examples of a pressurized gas recirculation systemin a gas enclosure system. First, under typical operation of a gasenclosure system without a pressurized non-reactive gas recirculationsystem, a gas enclosure system can be maintained at a slightly positiveinternal pressure (e.g., above atmospheric pressure) relative to anexternal pressure in order to safeguard against outside gas or air fromentering the interior should any leaks develop in a gas enclosuresystem. For example, under typical operation, for various examples of agas enclosure system of the present teachings, the interior of a gasenclosure system can be maintained at a pressure relative to thesurrounding atmosphere external to the enclosure system, for example, ofat least 2 mbarg, for example, at a pressure of at least 4 mbarg, at apressure of at least 6 mbarg, at a pressure of at least 8 mbarg, or at ahigher pressure.

Maintaining a pressurized gas recirculation system within a gasenclosure system can be challenging, as it presents a dynamic andongoing balancing act regarding maintaining a slight positive internalpressure of a gas enclosure system, while at the same time continuouslyintroducing pressurized gas into a gas enclosure system. Further,variable demand of various devices and apparatuses can create anirregular pressure profile for various gas enclosure assemblies andsystems of the present teachings. Maintaining a dynamic pressure balancefor a gas enclosure system held at a slight positive pressure relativeto the external environment under such conditions can provide for theintegrity of an ongoing fabrication process. For various examples of agas enclosure system, a pressurized gas recirculation system accordingto the present teachings can include various examples of a pressurizedgas loop that can utilize at least one of a compressor, an accumulator,and a blower, and combinations thereof. Various examples of apressurized gas recirculation system that include various examples of apressurized gas loop can have a specially designed pressure-controlledbypass loop that can provide internal pressure of a non-reactive gas ina gas enclosure system of the present teachings at a stable, definedvalue. In various examples of a gas enclosure system, a pressurized gasrecirculation system can be configured to re-circulate pressurized gasvia a pressure-controlled bypass loop when a pressure of a gas in anaccumulator of a pressurized gas loop exceeds a pre-set thresholdpressure. The threshold pressure can be, for example, within a rangefrom between about 25 psig to about 200 psig, or more specificallywithin a range of between about 75 psig to about 125 psig, or morespecifically within a range from between about 90 psig to about 95 psig.In that regard, a gas enclosure system of the present teachings having apressurized gas recirculation system with various examples of aspecially designed pressure-controlled bypass loop can maintain abalance of having a pressurized gas recirculation system in anhermetically sealed gas enclosure.

According to the present teachings, various devices and apparatuses canbe disposed in the interior of a gas enclosure system and in fluidcommunication with various examples of a pressurized gas recirculationsystem. For various examples of a gas enclosure and system of thepresent teachings, the use of various pneumatically operated devices andapparatuses can provide low-particle generating performance, as well asbeing low maintenance. Exemplary devices and apparatuses that can bedisposed in the interior of a gas enclosure system and in fluidcommunication with various pressurized gas loops can include, forexample, but not limited by, one or more of a pneumatic robot, asubstrate floatation table, an air bearing, an air bushing, a compressedgas tool, a pneumatic actuator, and combinations thereof. A substratefloatation table, as well as air bearings can be used for variousaspects of operating a printing system in accordance with variousexamples of a gas enclosure system of the present teachings. Forexample, a substrate floatation table utilizing air-bearing technologycan be used to transport a substrate into position in a printheadchamber, as well as to support a substrate during a printing process.

For example, as shown in FIGS. 21A, 21B, 22A, and 22B, various examplesof gas enclosure system 500C and gas enclosure system 500D can haveexternal gas loop 3200 for integrating and controlling a non-reactivegas source 3201 and clean dry air (CDA) source 3203 for use in variousaspects of operation of gas enclosure system 500C and gas enclosuresystem 500D. Gas enclosure system 500C and gas enclosure system 500D canalso include various examples of an internal particle filtration and gascirculation system, as well as various examples of an external gaspurification system, as previously described. Such examples of a gasenclosure system can include a gas purification system for purifyingvarious reactive species from a gas. Some commonly used non-limitingexamples of a non-reactive gas can include nitrogen, any of the noblegases, and any combination thereof. Various examples of a gaspurification system according to the present teachings can maintainlevels for each species of various reactive species, including variousreactive atmospheric gases, such as water vapor, oxygen, ozone, as wellas organic solvent vapors at 1000 ppm or lower, for example, at 100 ppmor lower, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1 ppm orlower. In addition to external loop 3200 for integrating and controllinggas source 3201 and CDA source 3203, gas enclosure system 500C and gasenclosure system 500D can have compressor loop 3250, which can supplygas for operating various devices and apparatuses that can be disposedin the interior of gas enclosure system 500C and gas enclosure system500D. A vacuum system 3270 can be also be provided, such as incommunication with gas enclosure assembly 1005 through line 3272 whenvalve 3274 is in an open position.

Compressor loop 3250 of FIG. 21A can include compressor 3262, firstaccumulator 3264 and second accumulator 3268, which are configured to bein fluid communication. Compressor 3262 can be configured to compressgas withdrawn from gas enclosure assembly 1005 to a desired pressure. Aninlet side of compressor loop 3250 can be in fluid communication withgas enclosure assembly 1005 via gas enclosure assembly outlet 3252through line 3254, having valve 3256 and check valve 3258. Compressorloop 3250 can be in fluid communication with gas enclosure assembly 1005on an outlet side of compressor loop 3250 via external gas loop 3200.Accumulator 3264 can be disposed between compressor 3262 and thejunction of compressor loop 3250 with external gas loop 3200 and can beconfigured to generate a pressure of 5 psig or higher. Secondaccumulator 3268 can be in compressor loop 3250 for providing dampeningfluctuations due to compressor piston cycling at about 60 Hz. Forvarious examples of compressor loop 3250, first accumulator 3264 canhave a capacity of between about 80 gallons to about 160 gallons, whilesecond accumulator can have a capacity of between about 30 gallons toabout 60 gallons. According to various examples of gas enclosure system500C, compressor 3262 can be a zero ingress compressor. Various types ofzero ingress compressors can operate without leaking atmospheric gasesinto various examples of a gas enclosure system of the presentteachings. Various examples of a zero ingress compressor can be runcontinuously, for example, during a fabrication process utilizing theuse of various devices and apparatuses requiring compressed gas.

Accumulator 3264 can be configured to receive and accumulate compressedgas from compressor 3262. Accumulator 3264 can supply the compressed gasas needed in gas enclosure assembly 1005. For example, accumulator 3264can provide gas to maintain pressure for various components of gasenclosure assembly 1005, such as, but not limited by, one or more of apneumatic robot, a substrate floatation table, an air bearing, an airbushing, a compressed gas tool, a pneumatic actuator, and combinationsthereof. As shown in FIG. 21A for gas enclosure system 500C, gasenclosure assembly 1005 can have printing system 2005 enclosed therein.As schematically depicted in FIG. 21A, printing system 2005 can besupported by printing system base 2150, which can be a granite stage.Printing system base 2150 can support a substrate support apparatus,such as a chuck, for example, but not limited by, a vacuum chuck, asubstrate floatation chuck having pressure ports, and a substratefloatation chuck having vacuum and pressure ports. In various examplesof the present teachings, a substrate support apparatus can be asubstrate floatation table, such as substrate floatation table 2250.Substrate floatation table 2250 can be used for the frictionless supportof a substrate. In addition to a low-particle generating floatationtable, for frictionless Y-axis conveyance of a substrate, printingsystem 2005 can have a Y-axis motion system utilizing air bushings.

Additionally, printing system 2005 can have at least one X,Z-axiscarriage assembly with motion control provided by a low-particlegenerating X-axis air bearing assembly. Various components of alow-particle generating motion system, such as an X-axis air bearingassembly, can be used in place of, for example, variousparticle-generating linear mechanical bearing systems. For variousexamples of a gas enclosure and system of the present teachings, the useof a variety of pneumatically operated devices and apparatuses canprovide low-particle generating performance, as well as being lowmaintenance. Compressor loop 3250 can be configured to continuouslysupply pressurized gas to various devices and apparatuses of gasenclosure system 500C. In addition to a supply of pressurized gas,substrate floatation table 2250 of printing system 2005, which utilizesair bearing technology, also utilizes vacuum system 3270, which is incommunication with gas enclosure assembly 1005 through line 3272 whenvalve 3274 is in an open position.

A pressurized gas recirculation system according to the presentteachings can have pressure-controlled bypass loop 3260 as shown in FIG.21A for compressor loop 3250, which acts to compensate for variabledemand of pressurized gas during use, thereby providing dynamic balancefor various examples of a gas enclosure system of the present teachings.For various examples of a gas enclosure system according to the presentteachings, a bypass loop can maintain a constant pressure in accumulator3264 without disrupting or changing the pressure in enclosure 1005.Bypass loop 3260 can have first bypass inlet valve 3261 on an inlet sideof bypass loop, which is closed unless bypass loop 3260 is used. Bypassloop 3260 can also have back pressure regulator 3266, which can be usedwhen second valve 3263 is closed. Bypass loop 3260 can have secondaccumulator 3268 disposed at an outlet side of bypass loop 3260. Forexamples of compressor loop 3250 utilizing a zero ingress compressor,bypass loop 3260 can compensate for small excursions of pressure thatcan occur over time during use of a gas enclosure system. Bypass loop3260 can be in fluid communication with compressor loop 3250 on an inletside of bypass loop 3260 when bypass inlet valve 3261 is in an openedposition. When bypass inlet valve 3261 is opened, gas shunted throughbypass loop 3260 can be recirculated to the compressor if gas fromcompressor loop 3250 is not in demand within the interior of gasenclosure assembly 1005. Compressor loop 3250 is configured to shunt gasthrough bypass loop 3260 when a pressure of the gas in accumulator 3264exceeds a pre-set threshold pressure. A pre-set threshold pressure foraccumulator 3264 can be from between about 25 psig to about 200 psig ata flow rate of at least about 1 cubic feet per minute (cfm), or frombetween about 50 psig to about 150 psig at a flow rate of at least about1 cubic feet per minute (cfm), or from between about 75 psig to about125 psig at a flow rate of at least about 1 cubic feet per minute (cfm)or between about 90 psig to about 95 psig at a flow rate of at leastabout 1 cubic feet per minute (cfm).

Various examples of compressor loop 3250 can utilize a variety ofcompressors other than a zero ingress compressor, such as a variablespeed compressor or a compressor that can be controlled to be in eitheran on or off state. As previously discussed herein, a zero ingresscompressor ensures that no atmospheric reactive species can beintroduced into a gas enclosure system. As such, any compressorconfiguration preventing atmospheric reactive species from beingintroduced into a gas enclosure system can be utilized for compressorloop 3250. According to various examples, compressor 3262 of gasenclosure system 500C can be housed in, for example, but not limited by,an hermetically-sealed housing. The housing interior can be configuredin fluid communication with a source of gas, for example, the same gasthat forms the gas atmosphere for gas enclosure assembly 1005. Forvarious examples of compressor loop 3250, compressor 3262 can becontrolled at a constant speed to maintain a constant pressure. In otherexamples of compressor loop 3250 not utilizing a zero ingresscompressor, compressor 3262 can be turned off when a maximum thresholdpressure is reached, and turned on when a minimum threshold pressure isreached.

In FIG. 22A for gas enclosure system 500D, blower loop 3280 utilizingvacuum blower 3290 is shown for the operation of substrate floatationtable 2250 of printing system 2005, which are housed in gas enclosureassembly 1005. As previously discussed herein for compressor loop 3250,blower loop 3280 can be configured to continuously supply pressurizedgas to a substrate floatation table 2250 of printing system 2005.

Various examples of a gas enclosure system that can utilize apressurized gas recirculation system can have various loops utilizing avariety of pressurized gas sources, such as at least one of acompressor, a blower, and combinations thereof. In FIG. 22A for gasenclosure system 500D, compressor loop 3250 can be in fluidcommunication with external gas loop 3200, which can be used for thesupply of gas for high consumption manifold 3225, as well as lowconsumption manifold 3215. For various examples of a gas enclosuresystem according to the present teachings as shown in FIG. 22A for gasenclosure system 500D, high consumption manifold 3225 can be used tosupply gas to various devices and apparatuses, such as, but not limitedby, one or more of a substrate floatation table, a pneumatic robot, anair bearing, an air bushing, and a compressed gas tool, and combinationsthereof. For various examples of a gas enclosure system according to thepresent teachings, low consumption 3215 can be used to supply gas tovarious apparatuses and devises, such as, but not limited by, one ormore of an isolator, and a pneumatic actuator, and combinations thereof.

For various examples of gas enclosure system 500D of FIGS. 22A and 22B,a blower loop 3280 can be utilized to supply pressurized gas to variousexamples of substrate floatation table 2250. In addition to a supply ofpressurized gas, substrate floatation table 2250 of printing system2005, which utilizes air bearing technology, also utilizes blower vacuum3290, which is in communication with gas enclosure assembly 1005 throughline 3292 when valve 3294 is in an open position. Housing 3282 of blowerloop 3280 can maintain first blower 3284 for supplying a pressurizedsource of gas to substrate floatation table 2250, and second blower3290, acting as a vacuum source for substrate floatation table 2250,which is housed in a gas environment in gas enclosure assembly 1005.Attributes that can make blowers suitable for use as a source of eitherpressurized gas or vacuum for various examples a substrate floatationtable include, for example, but not limited by, that they have highreliability; making them low maintenance, have variable speed control,and have a wide range of flow volumes; various examples capable ofproviding a volume flow of between about 100 m³/h to about 2,500 m³/h.Various examples of blower loop 3280 additionally can have firstisolation valve 3283 at an inlet end of blower loop 3280, as well ascheck valve 3285 and a second isolation valve 3287 at an outlet end ofblower loop 3280. Various examples of blower loop 3280 can haveadjustable valve 3286, which can be, for example, but not limited by, agate, butterfly, needle or ball valve, as well as heat exchanger 3288for maintaining gas from blower loop 3280 to substrate floatation table2250 at a defined temperature.

FIG. 22A depicts external gas loop 3200, also shown in FIG. 21A, forintegrating and controlling gas source 3201 and clean dry air (CDA)source 3203 for use in various aspects of operation of gas enclosuresystem 500C of FIG. 21A and gas enclosure system 500D of FIG. 22A.External gas loop 3200 of FIG. 21A and FIG. 22A can include at leastfour mechanical valves. These valves include first mechanical valve3202, second mechanical valve 3204, third mechanical valve 3206, andfourth mechanical valve 3208. These various valves are located atpositions in various flow lines that allow control of both anon-reactive gas and an air source such as clean dry air (CDA).According to the present teachings, a non-reactive gas can be any gasthat does not undergo a chemical reaction under a defined set ofconditions. Some commonly used non-limiting examples of non-reactive gascan include nitrogen, any of the noble gases, and any combinationthereof. From a house gas source 3201, a house gas line 3210 extends.House gas line 3210 continues to extend linearly as low consumptionmanifold line 3212, which is in fluid communication with low consumptionmanifold 3215. A cross-line first section 3214 extends from a first flowjuncture 3216, which is located at the intersection of house gas line3210, low consumption manifold line 3212, and cross-line first section3214. Cross-line first section 3214 extends to a second flow juncture3218. A compressor gas line 3220 extends from accumulator 3264 ofcompressor loop 3250 and terminates at second flow juncture 3218. A CDAline 3222 extends from a CDA source 3203 and continues as highconsumption manifold line 3224, which is in fluid communication withhigh consumption manifold 3225. A third flow juncture 3226 is positionedat the intersection of a cross-line second section 3228, clean dry airline 3222, and high consumption manifold line 3224. Cross-line secondsection 3228 extends from second flow juncture 3218 to third flowjuncture 3226. Various components that are high consumption can besupplied CDA during maintenance, by means high consumption manifold3225. Isolating the compressor using valves 3204, 3208, and 3230 canprevent reactive species, such as ozone, oxygen, and water vapor fromcontaminating a gas within the compressor and accumulator.

By contrast with FIGS. 21A and 22A, FIGS. 21B and 22B illustrategenerally a configuration wherein a pressure of gas inside the gasenclosure assembly 1005 can be maintained within a desired or specifiedrange, such as using a valve coupled to a pressure monitor, P, where thevalve allows gas to be exhausted to another enclosure, system, or aregion surrounding the gas enclosure assembly 1005 using informationobtained from the pressure monitor. Such gas can be recovered andre-processed as in other examples described herein. As mentioned above,such regulation can assist in maintaining a slight positive internalpressure of a gas enclosure system, because pressurized gas is alsocontemporaneously introduced into the gas enclosure system. Variabledemand of various devices and apparatuses can create an irregularpressure profile for various gas enclosure assemblies and systems of thepresent teachings. Accordingly, the approach shown in FIGS. 21B and 22Bcan be used in addition or instead of other approaches described hereinsuch as to assist in maintaining a dynamic pressure balance for a gasenclosure system held at a slight positive pressure relative to theenvironment surrounding the enclosure.

FIG. 22C illustrates generally a further example of a system 500E forintegrating and controlling one or more gas or air sources, such as toestablish floatation control zones included as a portion of a floatationconveyance system. Similar to the examples of FIG. 1C, FIG. 22A and FIG.22B, FIG. 22C illustrates generally floatation table 2250. Additionallyshown in the illustrative example of FIG. 22C are an input region 2201and an output region 2203. The regions 2201, 2200, 2203 are referred toas input, printing, and output for illustration only. Such regions canbe used for other processing steps, such as conveyance of a substrate,or support of a substrate such as during one or more of holding, drying,or thermal treatment of the substrate in one or more other modules. Inthe illustration of FIG. 22C, a first blower 3284A is configured toprovide pressurized gas in one or more of the input or output regions2201 or 2203 of a floatation table apparatus. Such pressurized gas canbe temperature controlled such as using a first chiller 142A coupled toa first heat exchanger 1502A. Such pressurized gas can be filtered usinga first filter 1503A. A temperature monitor 8701A can be coupled to thefirst chiller 142 (or other temperature controller).

Similarly, a second blower 3284B can be coupled to the printing region2202 of the floatation table. A separate chiller 142B can be coupled toa loop including a second heat exchanger 1502B and a second filter1503B. A second temperature monitor 8701B can be used to provideindependent regulation of the temperature of pressurized gas provided bythe second blower 3284B. In this illustrative example, as previouslydescribed herein for FIG. 1C, the input and output regions 2201 and 2203are supplied with positive pressure, but the printing region 2202 caninclude use of a combination of positive pressure and vacuum control toprovide precise control over the substrate position. For example, usingsuch a combination of positive pressure and vacuum control, thesubstrate can be exclusively controlled using the floating gas cushionprovided by gas enclosure system 500D in the zone defined by theprinting region 2202. The vacuum can be established by a third blower3290, such as also provided at least a portion of the make-up gas forthe first and second blowers 3284A or 3284B within the blower housing3282.

It should be understood that various alternatives to the embodiments ofthe disclosure described herein may be employed in practicing thedisclosure. For example, while vastly different arts such as chemistry,biotechnology, high technology and pharmaceutical arts may benefit fromthe present teachings. Printing is used to exemplify the utility ofvarious embodiments of a gas enclosure system according to the presentteachings. Various embodiments of a gas enclosure system that may housea printing system can provide features such as, but not limited by,sealing providing an hermetic-sealed enclosure through cycles ofconstruction and deconstruction, minimization of enclosure volume, andready access from the exterior to the interior during processing, aswell as during maintenance. Such features of various embodiments of agas enclosure system may have an impact on functionality, such as, butnot limited by, structural integrity providing ease of maintaining lowlevels of reactive species during processing, as well as rapidenclosure-volume turnover minimizing downtime during maintenance cycles.As such, various features and specifications providing utility forsubstrate printing may also provide benefit to a variety of technologyareas.

While embodiments of the present disclosure have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the disclosure. It is intended thatthe following claims define the scope of the disclosure and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

1-5. (canceled)
 6. A method of controlling motion of a printheadassembly: receiving input of a commanded Z-axis position for a printheadassembly mounted to a Z-axis moving plate assembly of an X-Z motionsystem; in response to receiving the input, supplying an input currentto a drive motor operably coupled to the Z-axis moving plate assembly tomove the Z-axis moving plate assembly in a Z-direction; monitoring theinput current to the drive motor; and based on the monitoring of theinput current, controlling operation of a pneumatic counterbalancesystem operably coupled to the Z-axis moving plate assembly.
 7. Themethod of claim 6, wherein controlling operation of the pneumaticcounterbalance system comprises controlling a pressure of the pneumaticcounterbalance system.
 8. The method of claim 6, wherein the commandedZ-axis position corresponds to a position of the printhead assemblyduring a maintenance operation being performed on the printheadassembly.
 9. The method of claim 6, wherein supplying the input currentto the drive motor causes the Z-axis moving plate assembly to move in afirst Z-direction.
 10. The method of claim 9, wherein monitoring theinput current occurs during application of a force on the Z-axis movingplate assembly in a direction opposite to the first Z-direction.
 11. Themethod of claim 10, wherein the force is a sealing force generated bydocking of the printhead assembly during a maintenance operation on theprinthead assembly.
 12. The method of claim 6, further comprising:calculating a pneumatic counterforce sufficient to offset a load on themotor, the calculating of the pneumatic counterforce being based on themonitoring of the input current.
 13. The method of claim 12, furthercomprising controlling the pneumatic counterbalance system to apply thepneumatic counterforce to the Z-axis moving plate assembly.
 14. Themethod of claim 6, further comprising: prior to supplying the inputcurrent to the drive motor: receiving additional input of a commandedX-axis position for the printhead assembly; and in response to receivingthe additional input, actuating an X-axis motion system to move theprinthead assembly to the commanded X-axis position.
 15. The method ofclaim 14, wherein supplying the input current to the drive motor causesthe Z-axis moving plate assembly to move the printhead assembly to thecommanded Z-axis position while remaining in the commanded X-axisposition.
 16. The method of claim 6, wherein the method of controllingoperation of the printhead assembly is performed while the printheadassembly is in an enclosed, thermally controlled substrate printingenvironment.
 17. The method of claim 16, wherein the process environmentis an inert gas environment.
 18. A method of controlling operation of aprinthead assembly, comprising: moving a Z-axis moving plate assembly ofan X-Z axis motion system to move a printhead assembly in a firstZ-direction to a commanded position, the printhead assembly beingcoupled to the Z-axis moving plate assembly; with the printhead assemblyin the commanded position, actuating a motor to exert a first force onthe Z-axis moving plate assembly in the first Z-direction while a secondforce acts on the Z-axis moving plate assembly, the second force beingin a second Z-direction opposite to the first Z-direction; and actuatinga pneumatic counterbalance system to maintain the first force on theZ-axis moving plate while the second force continues to act on theZ-axis moving plate assembly.
 19. The method of claim 18, wherein thecommanded position is a docked position of the printhead assembly duringa maintenance operation on the printhead assembly.
 20. The method ofclaim 19, wherein the second force is a sealing force generated fromdocking the printhead assembly against a sealing structure during themaintenance operation on the printhead assembly.
 21. The method of claim18, wherein actuating the pneumatic counterbalance system comprisesincreasing a pneumatic pressure of the pneumatic counterbalance system.22. The method of claim 18, wherein actuating the motor comprisessupplying current to the motor.
 23. The method of claim 22, furthercomprising reducing the current supplied to the motor after theactuating of the pneumatic counterbalance system.
 24. The method ofclaim 18, further comprising supporting a substrate in a gas enclosure,the printhead assembly being used in the gas enclosure for printing thesubstrate, wherein a surface of the substrate to be printed lies in anX-Y plane and the Z-direction is defined perpendicular to the X-Y plane.25. The method of claim 24, further comprising maintaining a thermallycontrolled environment in the gas enclosure.
 26. The method of claim 25,wherein the thermally controlled environment is an inert gasenvironment.
 27. The method of claim 25, wherein supporting thesubstrate in the gas enclosure comprises supporting the substrate viafloatation in the gas enclosure.
 28. The method of claim 18, furthercomprising moving the Z-axis moving plate assembly to place theprinthead assembly at a commanded X-axis position.